Grade 10 Physical Sciences Lesson Plans · PDF fileLearners observe the experiment/ record...

GRADE 10 SUBJECT Physical Sciences WEEK 14 TOPIC Physical and Chemical change

(chemical change) - Time: 60 minutes Lesson 1&2

LESSON SUMMARY FOR: DATE STARTED: DATE COMPLETED:

LESSON OBJECTIVES

At the end of this lesson learners should be able to: Describe what happens to matter when it undergoes a chemical change. List examples of chemical changes that matter undergoes. The following results will be the outcome of this lesson: To re-enforce the concepts of physical and chemical change. The learners being able to describe and explain the chemical changes that elements and compounds undergo.

TEACHING and LEARNING ACTIVITIES

1. TEACHING METHOD/S USED IN THIS LESSON:

Question and Answer; Narrative

2. LESSON DEVELOPMENT

2.1 Introduction

Introduce the lesson with an exciting demonstration/ experiment OR explain an example where the lesson is applied to life in general.

e.g. Half fill a test tube with HYDROGEN PEROXIDE liquid, wait a few minutes and note what happens. Add a pinch of manganese dioxide and note what happens.

Learners observe the experiment/ record their results and observations/ listen and follow demonstration. [20 min.]

PRE-KNOWLEDGE

A basic understanding of :

Atoms; molecules ; compounds and elements

Matter and the different phases in which it is found in.

Chemical changes and how to explain what happens in a chemical change.

EDUCATOR tests pre-knowledge by using the question and answer method as indicated in the baseline assessment.

BASELINE ASSESSMENT: QUESTIONS/ ACTIVITY [10 min.]

What is matter? What are the components of matter? What are the different phases of matter?

What are atoms? Give examples.

Grade 10 Physical Sciences Lesson Plans

Term 2 © Gauteng Department of Education (ver.1)

What are molecules? Give examples.

What is a physical change and list examples of physical changes.

What is a chemical change and give examples of chemical changes.

2.2 Main Body (Lesson presentation)

Educator starts lesson off with an exciting demonstration as mentioned in the introduction and explains the relevant concepts in terms of a chemical change. [20 min.]

Matter is all around us and it undergoes changes all the time, these changes can be classified as PHYSICAL CHANGES OR CHEMICAL CHANGES.

The CONCEPTS of PHYSICAL CHANGE and CHEMICAL CHANGE is shown in the table below, educator engages learners in a discussion of the different aspects of physical and

chemical change as mentioned in the table to re-enforce the concepts.

physical changes chemical changes

common signs that a chemical change has occurred are: 1. Production of gas bubbles 2. Change in the way something smells 3. A release of energy such as a flash or a sound (like a firecracker) 4. A precipitate forms (two liquids mixed together form a solid and a liquid)

common signs that a physical change has occurred are: 1. change in the size 2. change in shape, 3. change in colour, or 4. Change in state/ phase of matter of a substance. 5. No new substance is produced.

Examples of physical changes Examples of chemical changes

• A grape when stepped on (changes shape) Blowing up a balloon (changes size and shape) • Liquid water turning to ice (changes state of matter) • Liquid water turning to steam (changes state of matter) • Mixing salt and sugar (changes the appearance, but you can still separate the mixture) • Mixing water and salt (changes the appearance, but you can still separate the mixture)

Metal rusting (new substance formed) • Stomach digesting food (break down of food to new substances) • Plant carrying out photosynthesis (putting water and carbon dioxide together to make sugar) • Mixing baking soda and vinegar (makes a neutral liquid and a gas)

Educator discusses the results of the experiment with the learners.

The liquid hydrogen peroxide decomposes (breaks up) to form oxygen gas and liquid water (The atomic model the using ball and stick as well as space filling diagrams to show

the reactants and products in this reaction).

The MANGANESE DIOXIDE is a catalyst and speeds up the reaction. A CATALYST is a chemical substance that changes the speed of a reaction without getting used up in the

process, at the end of the reaction the catalyst can be recovered. Eg. ENZYMES in our body help to speed up the digestive process.



Educator engages learners in a question and answer session with regards the observations they have made. What do the products look like? How are they different from the

original substances in terms of colour; phase; feel; smell etc.? Do the products have any of the properties of the original reactant, eg? Hydrogen peroxide is highly corrosive

(burns your skin burning sensation), can be used as a bleaching agent (removes colour/ cleaning of metals)

3. Conclusion and Chalkboard summary

Activity to Re-enforce lesson (Educator explains main concepts of the lesson and summarises points on chalkboard. (CHALKBOARD SUMMARY). [10 min.]

During a Chemical change the particles themselves are changed in some way. There are greater energy changes that take place in a chemical change as compared to a

physical change. The changes in energy are because energy is needed to break up bonds and then energy is given off when bonds are formed in the new products. It is very

difficult to reverse a chemical change as can be seen from the fried egg that forms when the liquid egg is heated.

In most chemical changes that take place the total mass remains of the reactants and products remain the same but the number of atoms and molecules change as shown

below:

HOMEWORK QUESTIONS/ ACTIVITY (educator must give learners a few questions to answer at home by either writing them on the chalkboard or giving an exercise from the

prescribed textbook) [10 min]

Hydrogen Peroxide 2 hydrogens: 2 oxygens

Water 2 hydrogens : 1 oxygen

Oxygen gas 2 oxygens

Hydrogen Peroxide 2 hydrogens: 2 oxygens

Water 2 hydrogens : 1 oxygen

Oxygen gas 2 oxygens



Reflection/Notes:

Name of Teacher: HOD:

Sign: Sign:

Date: Date:

i.e. 1. For each of the following say whether a CHEMICAL CHANGE or a PHYSICAL CHANGE occurs: 1.1 Melting candle wax. 1.2 Mixing sodium chloride and silver nitrate to form

silver chloride and sodium nitrate. 1.3 Dissolving salt in water. 1.4 Melting a piece of plastic. 1.5 Burning a piece of paper.

2. Explain your answer for each of the changes that took place in the situations from 1.1 To 1.5.

RESOURCES USED:

Relevant apparatus (models/ atomic kits) and chemicals for practical demonstration; worksheet/ transparency for baseline assessment; relevant textbook/ notes eg (CAPS

document pg. 35-37; chapter 12 from textbook PHYSICAL SCIENCES 10 pg. 109-113 (platinum series- Grayson; Harris; Mckenzie and Schreuder); grade 10 physical science version 1

caps pg. 192-196(Siyavula and volunteers).



GRADE 10 SUBJECT Physical Sciences WEEK 15 TOPIC Physical and Chemical change (conservation

of matter) – Time: 60 minutes Lesson 1


LESSON OBJECTIVES

At the end of this lesson learners should be able to: Illustrate the conservation of atoms and the non-conservation of molecules using atomic model diagrams (ball and stick and space filling) The following results will be the outcome of this lesson: To re-enforce the concepts of physical and chemical change. The learners being able to use atomic models and diagrams to describe and explain the chemical changes that elements and compounds

undergo.





2.1 Introduction:

Educator introduces the lesson with an exciting demonstration/ experiment OR explains an example where the lesson is applied to life in general.

eg: Use the atomic model kit if available or use toothpicks and jelly tots to build the atomic/ molecular models for the reaction for the formation of the water molecule from the

hydrogen molecule and the oxygen molecule and also build models for the decomposition of hydrogen peroxide reaction. Use these models to show the conservation of atoms

and the non-conservation of molecules in a physical change.


PRE-KNOWLEDGE








What is m

What are

What are

What is a

What is a

2.2 Main Bo

Educator e

In a chemic

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The LAW

elemen

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a chemical chang

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W of CONSERVATIO

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OTAL NUMBER of A

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phases of matter?

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e NUMBER of MOLE

of hydrogen perox

ounds bond to form

ED in a CHEMICAL

O2 →

2 Water molecuatom = 6 atoms

rams and equatio

ECULES may CHAN

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m new products in

L REACTION.

2H2O

les = 4 hydrogen a

ons. [20 min.]

NGE as seen below

n a chemical reac

atoms + 2 oxygen

w in the reaction e

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equations for the

of atoms of each

en molecule gen atoms

type of



CLOSED SYSTEM is when no outside factors (heat, other substances etc.) are added to the reaction to change the conditions to affect the reaction. Eg. Container must be

closed when gases are involved.



During a Chemical change the particles themselves are changed in some ways. There are greater energy changes that take place in a chemical change as compared to a

physical change. The changes in energy are because energy is needed to break up bonds and then energy is given off when bonds are formed in the new products. It is very

difficult to reverse a chemical change as can be seen from the fried egg that forms when the liquid egg is heated. The total mass remains constant but the number of atoms

and molecules change in most chemical reactions as shown above in the ball and stick and space filling models in the reaction with hydrogen peroxide.



i.e. 1. Copy the following diagrams in your books and complete the parts of the atoms and molecules that are missing.

3H2 + N2 2NH3 3 molecules of hydrogen gas 1 molecule of nitrogen gas 2 molecules of ammonia 6 atoms of hydrogen 2 atoms of nitrogen 6 atoms of hydrogen and 2 atoms of nitrogen

2SO2 + O2 2SO3 2 molecules of sulphur dioxide gas 1 molecule of oxygen gas 2 molecules of ammonia 2 atoms of sulphur and 2 atoms of oxygen 2 atoms of sulphur and 4 atoms of oxygen 6 atoms of oxygen



2. Draw the ball and stick models for the following chemical equations: Balance the following equations. All the reactants and products are shown.

2.1 Magnesium is burned in oxygen to give magnesium oxide: 2.2 Carbon and chlorine gas react to form carbon tetrachloride:

2.3 Potassium oxide is formed by burning potassium in oxygen: K + O2 K2O

2.4 Hydrogen reacts with chlorine gas to form hydrogen chloride:

3. Now balance the number of atoms and molecules on the product side and the reactants side of the equation. Draw the ball and stick models for the above balanced chemical equations:

RESOURCES USED:




HYDROGEN GAS + OXYGEN GAS WATER



Reflection/Notes:


Sign: Sign:

Date: Date:




(experiment) – Time: 60 minutes Lesson 3&4


LESSON OBJECTIVES

At the end of this lesson learners should be able to: Illustrate the conservation of atoms and the non-conservation of molecules using an experiment. The following results will be the outcome of this lesson: To re-enforce the concepts of physical and chemical change. The learners being able to use atomic models and diagrams to describe and explain the chemical changes that elements and compounds

undergo.





2.1 Introduction:


eg: Use the experiment between lead ii nitrate and sodium iodide OR sodium hydroxide and hydrochloric acid OR reacting Cal-C-Vita tablets with water to show the conservation

of matter. The following apparatus and chemicals are needed: test tubes (4); 2 glass beakers; the respective chemicals; spatula (plastic spoons); 1 test tube stand; mass-meter;

rubber stoppers.


PRE-KNOWLEDGE


Atoms; molecules; compounds and elements.



BASELINE ASSESSMENT : QUESTIONS/ ACTIVITY [10 min.]









Educator starts lesson off with an exciting demonstration about atoms and molecules using the experiment mentioned in the introduction and explains all the relevant concepts.

[20 min.]

METHOD for the experiment: Educator measures approximately 5 g of each substance OR uses 1/3 of a teaspoon of the lead ii nitrate and the sodium iodide powder in each test

tube and fills the test tube up to the ¾ mark with water. The contents of the test tube are then shaken vigorously to dissolve the chemicals, use a rubber stopper to close the test

tube before shaking it. If possible measure the mass of all the test tubes with their contents and record this mass. To a third test tube add ½ of the contents of each test tube to the

third test tube and note your observations. Educator repeats experiment to make sure of results.

After a few seconds a solid starts forming in the solution, this solid has a yellow colour and is the lead iodide that forms a precipitate because it in insoluble in water. Now measure

the mass of each test tube after the reaction has taken place and compares it to the total mass before the reaction took place.

Educator divides class into groups of 4 to 6 learners, depending on how many sets of apparatus he has. The learners then carry out the experiments in their groups and record their

observations in the following table: [20 min.]

mass of reactants and water mass of products and water

REACTION 1

REACTION 2



Educator explains the LAW of CONSERVATION of MATTER using the BALANCED EQUATION as shown below.

In a chemical reaction the TOTAL NUMBER of ATOMS remains CONSTANT before and after the reaction takes place. The number of REACTANT ATOMS is equal to the number of

PRODUCT ATOMS. The TOTAL MASS at the start of the reaction is the same at the end of the reaction.



Reflection/Notes:


Sign: Sign:

Date: Date:



1. For each of the following definitions give the correct term:

1.1 a change that can be seen or felt where the particles are not broken up in any way. 1.2 The formation of new substances in a chemical reaction. 1.3 A reaction where a new

product is formed from elements or smaller compounds.

2. Explain how a chemical change differs from a physical change, give two examples to support your explanation.

RESOURCES USED:




Pb(NO3)2 + 2NaI 2 NaNO3 + PbI2

1 molecule of LEAD NITRATE 1 atom of lead + 2 atoms of nitrogen 6 atoms of oxygen

2 molecules of sodium iodide = 2 atoms of sodium + 2 atoms of iodine

2 molecules of SODIUM NITRATE 2 atoms of sodium + 2 atoms of nitrogen + 6 atoms of oxygen

1 molecule of LEAD IODIDE 1 atom of lead + 2 atoms of iodine




(chemical change reaction equations) Time: 60 minutes

Lesson 1


LESSON OBJECTIVES

At the end of this lesson learners should be able to: Represent chemical changes using reaction equations. Translate word equations into symbol representation using the correct symbols for the elements and compounds. The following results will be the outcome of this lesson: To re-enforce the concepts of physical and chemical change. The learners being able to describe and explain the chemical changes that elements and compounds undergo.





2.1 Introduction:



hydrogen molecule and the oxygen molecule. Use these models to show the conservation of atoms and the non-conservation of molecules in a chemical change as well as the

conservation of mass using symbols in a chemical equation. [20 min.]

PRE-KNOWLEDGE



Matter and the different phases in which it is found in.












Educator starts lesson by explaining the different components of a chemical equation. [20 min.]

In a chemical reaction the REACTANTS are the chemicals that are put in a container at the start of the reaction. The reaction then takes place to form the PRODUCTS which is

what is in the container after the reaction has taken place completely.

A CHEMICAL EQUATION is a SYMBOL REPRESENTATION of the chemical reaction. The REACTANTS are always shown on the left hand side of the equation and the PRODUCTS are

always on the right hand side. The ARROW that separates the reactants from the products shows the DIRECTION of the reaction. The LETTERS (s) indicates a SOLID; the letter (l) a

LIQUID; the letter (g) a GAS and the letters (aq) AQUEOUS..... these letters show the PHASE of the reactants and products in a chemical equation. In some reactions the ΔH is

shown which means the CHANGE in ENERGY of a particular reaction, the amount of energy that is given off or taken in a chemical reaction.

If the ΔH value is POSITIVE then the reaction is an ENDOTHERMIC REACTION, if it is a NEGATIVE value then the reaction is an EXOTHERMIC reaction.

ENDOTHERMIC REACTION is a reaction in which energy is absorbed from the surrounding for the reaction to take place, the temperature of the reaction mixture decreases as

the reaction takes place.

EXOTHERMIC REACTION is a reaction in which energy is given off to the surrounding, the temperature of the reaction mixture increases as the reaction takes place

The equations below show word equations which is then translated into chemical equations using the correct symbols for the elements and compounds.(the equations are not

balanced)

A(S) + B(l) C(g) + D(aq) ∆H = + 50 J

PHASE

Direction of

REACTANT PRODUCT

CHANGE IN ENERGY (Hproducts – Hreactants)

1. HYDROGEN GAS + OXYGEN GAS

H2(g) + O2 (g)

WATER

H2 O (l)



Reflection/Notes:


Sign: Sign:

Date: Date:



Educator discusses the writing of formulae with learners to re-enforce this skill. The following exercise is attempted by learners and then educator discusses answers on the board

using ionic equations and charges.

Learners to write down the chemical formula of the following compounds: 1. Sodium chloride 2. Magnesium fluoride 3. Potassium oxide 4. Aluminium oxide 5. Zinc nitrate 6.

Aluminium sulphate 7. Iron iii chloride 8. Potassium dichromate 9. Ammonium phosphate 10. Sulphur iv oxide


prescribed textbook) [10 min] i.e. Write down the correct chemical name for each of the following: 1. SO2 2. KMnO4 3. (NH4)2SO4 4. Fe3(PO4)2 5. KClO3

RESOURCES USED:




1.

2. HYDROGEN GAS + NITROGEN GAS AMMONIA

H2 + N2 NH3

3. SULPHUR DIOXIDE + OXYGEN SULPHUR TRIOXIDE SO2 + O2 SO3




(balanced reaction equations using atomic models) – Time: 60 minutes

lesson 2


LESSON OBJECTIVES

At the end of this lesson learners should be able to: Balance reaction equations using atomic models. Show the conservation of matter using balanced reaction equations. The following results will be the outcome of this lesson: To re-enforce the concepts of physical and chemical change. The learners being able to describe and explain the chemical changes that elements and compounds undergo.





2.1 Introduction:

Educator introduces the lesson with an exciting demonstration/ experiment OR explain an example where the lesson is applied to life in general.


hydrogen molecule and the oxygen molecule . Use these models to show the conservation of atoms and the non-conservation of molecules in a chemical change. [20 min.]

PRE-KNOWLEDGE



The writing of chemical formulae using the table of ions.



List the components of a chemical equation.

The writing of chemical formulae using the table of ions.



2.2 Main Bo

Educator st

The LAW of

reaction eq

Educat

Hydr4 hyd

Hydroge4 hydrog

1.

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tarts lesson by exp

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2

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other relevant con

T the NUMBER of M

gen peroxide.

bove model.

atoms

3 molec8 atom

ms 1 O2 ox

3 molecule8 atoms

cepts. [20 min.]

MOLECULES may C

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3. Conclus

Activity to R

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HOMEWOR

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RK QUESTIONS/ AC

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Reflection/Notes:


Sign: Sign:

Date: Date:

RESOURCES USED:






GRADE 10 SUBJECT Physical Sciences WEEK 16 TOPIC Physical and Chemical change(balanced

reaction equations) - Time: 60 minutes Lesson 3


LESSON OBJECTIVES

At the end of this lesson learners should be able to: Write reaction equations from word equations and balance them. Show the conservation of matter using balanced reaction equations. The following results will be the outcome of this lesson: To re-enforce the concepts of physical and chemical change. The learners being able to describe and explain the chemical changes that elements and compounds undergo.





2.1 Introduction:



hydrogen molecule and the oxygen molecule . Use these models to show the conservation of atoms and the non-conservation of molecules in a chemical change using symbols in

a chemical equation, the chemical equation must match the number of atoms and molecules in the atomic models being built. Use these models to show how to balance an

equation. [20

PRE-KNOWLEDGE



The components of a chemical equation.



List the components of a chemical equation




What a

2.2 Main Bo

Educator st

balancing

2. Iron re

Fe (s)

Since 1 abalance

1. HYDRO

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RK QUESTIONS/ AC

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PRODUCT SIDE

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SUMMARY). [10 m

of the equation a

ght. To get four hyden atoms and 2x1=

nd 4 atoms of H.

chemicals in the re

lkboard or giving a

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Reflection/Notes:


Sign: Sign:

Date: Date:

Balance the following equations:

Balance the following chemical equations showing the conservation of atoms. 1. Fe + H2S04 Fe2(SO4)3 + H2 2. C2H6 + O2 H2O + CO2

3. KOH + H3PO4 K3PO4 + H2O

4. SnO2 + H2 Sn + H2O

5. NH3 + O2 NO + H2O

RESOURCES USED:






GRADE 10 SUBJECT Physical Sciences WEEK 16 TOPIC Physical and Chemical change (interpret balanced equations in terms of mass) – Time: 60 minutes

Lesson 4


LESSON OBJECTIVES

At the end of this lesson learners should be able to: Interpret balanced reaction equations in terms of the conservation of mass. Show the conservation of matter using balanced reaction equations. The following results will be the outcome of this lesson: To re-enforce the concepts of chemical change. The learners being able to explain balanced chemical equations in terms of mass.





2.1 Introduction:



hydrogen molecule and the oxygen molecule . Use these models to show the conservation of atoms and the non-conservation of molecules in a chemical change as well as the

conservation of mass using symbols in a chemical equation. [20 min.]

PRE-KNOWLEDGE :


How to write formulae of compounds and elements

The components of a chemical equation.

Calculating relative atomic mass of elements and compounds from the periodic table.



List the components of a chemical equation

Calculating relative atomic mass of elements and compounds using the periodic table.



2.2 Main Bo

Educat

balanc

shown

Law of

the tota

In a chemicin the react

Example 1:

Reactants :

Product: ASince the n

Example 2:

Reactants:

Product: ASince the tois not balan

Mass of ReaO atoms)

ody (Lesson prese

tor starts lesson by

cing of equations u

in the three exam

conversation of m

al mass of reactan

cal equation thentants must be equ

: Atomic mass of

tomic mass of proumber of atoms o

Atomic mass of re

tomic mass of prootal atomic mass onced. The equatio

actants in balance

entation)

y writing the chem

using the law of co

mples done below.

mass states that: M

nts.

n, the mass of the rual to the number

reactants = 56 +

oduct = 56 + 32 =of each element is

eactants = (1 + 1)

oduct = (1 + 1 + 16of the reactants a

on can be balance

ed equation: Atom

ical equations fro

onservation of ma

. [20 min.]

Mass can neither b

reactants must be of atoms of those

Fe + S

+ 32 = 88 g Num

= 88 g Number o the same in the re

H2 +

+ (16 + 16) = 34 g

6) = 18 g Number oand the products ised as follows:

mic mass of react

m word equations

ass. The relative at

be created nor des

e equal to the mase same elements in

→ FeS

mber of atoms of

of atoms of each eeactants and in th

O2 →

Number of atom

of atoms of each es not the same an

2 H2 +

tants = 2(1 + 1) + (1

s and showing lea

omic of each elem

stroyed during a c

ss of the productsn the products. So

each element in t

element in the prohe products, we sa

H2O

ms of each elemen

element in the prond since there are

O2 →

16 + 16) = 36 g N

arners how to write

ment in the reacta

chemical reaction

. In order to makeome examples are

the reactants: (1

ducts: (1 ×ay that the equatio

nt in the reactants

oducts: (2 × more oxygen ato

→ 2 H2O

umber of atoms o

e the formula of co

ants and the prod

n. During a chemic

sure that this is thee shown below:

× Fe) and (

Fe) and (1 on is balanced.

s: (2 × H

H) and (1 oms in the reactan

of each element in

ompounds . The ed

ucts are obtained

cal reaction total m

e case, the numb

(1 × S)

× S)

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× O) nts than there are i

n the reactants: (2

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O)

in the product, the

x 2 x H = 4 H) and

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c table as

s equal to

ch element

e equation

d (2 X O = 2



Mass of Proatoms)

Example 3:

NaOH + HC

Reactants :

Products : A

Since the n

3. Conclus

Activity to R

The followin

Worked ExaMethane re 1. Write t

CH4(g)

2. BalancLook aside. CCH4(g) This puadd aThe eq

Reactants :

Products : A

HOMEWOR

prescribed

oducts in balanced

Cl → NaCl + H

: Atomic mass of re

Atomic mass of pro

umber of atoms o

sion and Chalkbo

Re-enforce lesson

ng example is don

ample Problem eacts with oxygen

the unbalanced e + O2(g) → CO2(g)

ce the equation. at the equation anCorrect this by put + 2O2(g) → CO2(g) uts the hydrogen aa coefficient of 2 foquation is now ba

: Atomic mass of re

Atomic mass of pro

RK QUESTIONS/ AC

textbook) [20 min

d equation: Atom

H2O

eactants = (23 + 1

oducts = (23 + 35.

of each element is

ard summary

(Educator expla

ne on the board to

n to form carbon d

equation. + H2O(l)

nd see which elemtting a coefficient + 2H2O(l) atoms out of balaor the water. Remlanced. Be sure to

eactants = (12 + 4

oducts = (12 + 2 x

CTIVITY (educator

n]

mic mass of produc

6 + 1) + (1 + 35.5)

5) + (1 + 1 + 16) =

the same in the re

ains main concept

o re-enforce the sk

dioxide and water

ments are not bala of 2 in front of wa

nce. Now there amember, coefficieno double-check yo

4 x 1) + (2 x 16 x 2)

16) + (2 x 18) = 80

must give learners

ct = (1 + 1 + 16) = 1

= 76.5 g Number

76.5 g Number of

eactants and in th

ts of the lesson an

kills in the writing a

r. Write the balanc

anced. In this caseater and a 2 in fron

re four hydrogen nts are multipliers, our math!

= 80 g Number of

0 g Number of ato

s a few questions t

18 x 2 = 36 g Num

of atoms of each

atoms of each el

he products, we sa

d summarises poin

and balancing of c

ced equation that

e, there are two oxnt of the oxygen:

atoms on the left so if we write 2 H2

f atoms of each el

ms of each eleme

to answer at home

mber of atoms of e

element in the rea

ement in the prod

ay that the equatio

nts on chalkboard

chemical equatio

describes this rea

xygen atoms on th

and four hydrogeO it denotes 2x2=4

lement in the reac

ent in the products

e by either writing

ach element in th

actants: (1 × Na) +

ducts: (1 × Na) + (1

on is balanced.

d. (CHALKBOARD S

ons

action.

he left-hand side o

n atoms on the rig4 hydrogen atoms

ctants: (1 × C) + (4

s: (1 × C) + (4 × O)

them on the cha

he products: (2 x 2

+ (1 × O) + (2 × H)

1 × O) + (2 × H) +

SUMMARY). [10 m

of the equation a

ght. To get four hys and 2x1=2 oxyge

4 × H) + (4 × O)

) + (2 × H)

lkboard or giving a

x H = 4 H) and (2 X

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the



Reflection/Notes:


Sign: Sign:

Date: Date:

Balance the following chemical equations showing the conservation of mass of reactants and products. 1. Fe + H2S04 Fe2(SO4)3 + H2 2. C2H6 + O2 H2O + CO2

3. KOH + H3PO4 K3PO4 + H2O

4. SnO2 + H2 Sn + H2O

5. NH3 + O2 NO + H2O

RESOURCES USED:






GRADE 10 SUBJECT PHYSICAL SCIENCES WEEK 17 TOPIC Magnetic and non-magnetic

materials – Time: 60 minutes Lesson 1

LESSON SUMMARY FOR: DATE STARTED: 122222 DATE COMPLETED:

LESSON OBJECTIVES

1. Learners will be taught and learn the following concepts: Classification of materials as magnetic or non-magnetic Daily applications of magnets Magnetic field of a permanent magnet 2. The outcomes of the lesson are : At the end of the lesson learners should be able to : Test and classify materials as magnetic or non-magnetic Give examples of materials that are magnetic and materials that are non-magnetic Describe the daily applications of magnets Explain the magnetic field of a permanent magnet

TEACHER ACTIVITIES LEARNER ACTIVITIES TIMING RESOURCES NEEDED

1. Teaching methods Observation, Investigative and Question and answer 2. Lesson development: 2.1 Introduction a. Pre-knowledge required. The force of attraction and force of repulsion Classifying materials as metals or non-metals b. Baseline assessment Refer to learner activities c. Do corrections on the board explaining and clarifying misconceptions.


If enough magnets are available, learners should do this investigation themselves Put the iron nail and lower the bar magnet nearer the magnet Learners will record their observations Repeat the same steps for all materials listed on the resources column and

record the results on the structured form. e.g.

1. Baseline Activity 1 1.1 Define the term force 1.2 Name two types of contact forces that can be exerted on an object. 1.3 What happens to an Iron nail as the magnet is passed nearer the nail? 1.4 What happens to an plastic comb as the magnet is passed nearer the comb? 2.2 Demonstration Activity 2 2.1 Classify the following as magnetic or non magnetic. Use the table on the teacher’s presentation column.

Baseline:

5 min

Demonstration

25 min

Answering

10 min

Check the available resource like textbook, question papers etc

• Bar magnet

• Iron nails

• Copper pieces

• Zinc plate

• Plastic comb

• Glass



materials magnetic Non-magnetic Iron nails Copper pieces Zinc plate Plastic comb glass Wood and etc.

Learners will provide more examples of magnetic and non-magnetic materials

Place an iron nail on the table and pass a bar magnet 10 cm above the nail and ask learners to record their observations

Learners try to explain their observations and the teacher clarifies the concept

The teacher uses learners observations to explain the concept of magnetic field.

Some of materials of which the magnet is made are named in class. e.g. cobalt, nickel, iron and its ores (magnetite and hematite)

Learners list some daily applications of magnets .e.g. magnet strips on fridge doors, speakers, telephone etc

2.3 Conclusion

Summarise the lesson considering definition of a magnetic field, classification of materials as magnetic or non-magnetic, the earth’s magnetic field and the electric field. Applications and importance of magnets need to be emphasised at this stage

2.2 Other than examples given above, give two examples of magnetic substances and examples of non- magnetic substances. 2.3 Name and describe three different applications of the magnets.

Corrections :

10 min

Conclusion :

5 minutes

Learner’s questions

5 min

Homework :

30 min

• Wood

• Graphite

• aluminium



Reflection/Notes:


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Date: Date:



GRADE 10 SUBJECT PHYSICAL SCIENCES WEEK 17 TOPIC MAGNETIC FIELD OF A PERMANENT

MAGNET – Time: 60 minutes Lesson 2


LESSON OBJECTIVES

1. Learners will be taught and learn the following concepts: Magnet as an object with two poles Attraction and repulsion of magnetic poles Magnetic field pattern around a permanent magnet

2. The outcomes of the lesson are : At the end of the lesson learners should be able to : Describe a magnet as an object with two opposite poles Predict the behaviour of the magnets when they are brought close together Sketch the magnetic field patterns, showing the shape, size and direction of magnetic field


1. Teaching methods Demonstration, Observation, & Question and answer 2. Lesson development: 2.1 Introduction a. Pre-knowledge required. Magnetic and non-magnetic materials Attraction and repulsion forces as a result of magnetic field b. Baseline assessment Refer to learner activities c. Do corrections on the board explaining and clarifying misconceptions.


If enough magnets are available, learners should do this investigation themselves as groups Place an A4 size card paper on top of a bar magnet Evenly sprinkle iron filings over a sheet of card paper Tap the card lightly with your finger The iron filings now show the magnetic field pattern of a bar magnet Place the small compasses at various positions around the pattern to find

direction of the field lines From the observation of the field lines and compass directions, draw the

magnetic field lines around a bar magnet.

1. Baseline Activity 1 1.1 Where will the magnetic object get attracted to the magnet? 1.2 Which objects may be attracted to the magnet? 1.3 Define magnetic field 1.4 What is the magnet consist of? Name three substances 2.2 Demonstration Activity 2 2.1 Draw the field line pattern around the bar magnet 2.2 Which direction will the magnetic field lines of a bar magnet be pointing?

Baseline:

5 min

Demonstration

30 min

Answering questions

10 min

A4 paper size

Bar magnet

Iron filling

Several compasses



Repeat the same but with two bar magnets having their north poles facing

each other and draw the field pattern

Repeat the steps above but with the south pole of one magnet facing the

north pole of the second magnet and draw the field lines pattern Illustrate the attraction force shown by joined lines between magnets and

repulsion force shown by bending lines between the south poles of two magnets facing each other

2.3 Conclusion

Summarise the lesson considering shape size and direction of magnetic field lines. Indicate where the field is strong and where the field weak

2.3 Draw the field lines between unlike poles of the two bar magnets and explain whether the force experienced by the two magnets is attractive or repulsive 2.4 What will happen if a bar magnet is broken into two pieces right in the middle? Will it still have north pole and south pole or it will only be two separated poles? Explain

Corrections :

5 min

Conclusion :

5 minutes


5 min

Homework :

30 min



Reflection/Notes:


Sign: Sign:

Date: Date:



GRADE 10 SUBJECT PHYSICAL SCIENCES WEEK 17 TOPIC EARTH’S MAGNETIC FIELD – TIME: 60 MINUTES Lesson 3


LESSON OBJECTIVES

1. Learners will be taught and learn the following concepts: Direction of magnetic field of a bar magnet Comparison between Earth’s magnetic field and magnetic field of a bar magnet Magnetic poles and geographic poles 2. The outcomes of the lesson are : At the end of the lesson learners should be able to : Explain how the compass indicates the direction of a magnetic field Illustrate the difference between geographic poles and magnetic poles Name and describe phenomenon that are affected by earth’s magnetic field Discuss qualitatively how earth’s magnetic fields provide protection from solar winds


1. Teaching methods Demonstration, Observation, & Question and answer

2. Lesson development: 2.1 Introduction a. Pre-knowledge required. Magnetic field pattern of a permanent magnet Poles of a magnet b. Baseline assessment Refer to learner activities c. Do corrections on the board explaining and clarifying misconceptions.


Demonstrate how the compass is used to find the direction of field lines around a bar magnet

Use diagrams to indicate magnetic field lines around a bar magnet as in the

previous lesson Compare the bar magnet with the earth as a big magnet, but be cautious

that learners should not misunderstand you in terms of magnetic poles and geographic poles

1. Baseline Activity 1 1.1 Define magnetic field 1.2 Draw the magnetic field lines around a bar magnet and show the direction of the field 1.3 What are the two poles of a bar magnet? 2.2 Demonstration Activity 2 2.1 What is meant by the solar winds? 2.2 Describe briefly how the earth’s magnetic field provides protection from solar winds 2.3 How does Aurora Borealis (Northern lights) occur?

Baseline: 5 min

Demonstration

30 min

Answering questions

7 min



Demonstrate the difference between the geographic poles and the

magnetic pole Illustrate that the magnetic poles also move about slightly over the time Use the earth’s magnetic field to explain the lights seen on the northern side

due to objects sent off from the sun and the earths atmosphere - Northern lights(Aurora Borealis)

Explain how animals migration is influenced by the earth’s magnetic field. (

Magnetite Fe3O4 ) was found on the heads of animals and flies). Assumption is that they use the earth’s magnetic field to navigate their journeys

2.3 Conclusion

Summarise the lesson explaining the earth as the big magnet. The earth behaves like a bar magnet and has poles. The difference between magnetic field of a bar magnet and earth’s magnetic field are explained. Explain the Aurora Borealis and the solar winds. Use geographical migration in certain seasons to emphasise ability of animals and flies to navigate using magnetic field

2.4 Which molecules helps the animals to migrate in the earth’s magnetic field since they do not have compass and navigators like people? 2.5 Compare the magnetic field of the earth to the magnetic field of a bar magnet.

Corrections : 8 min

Conclusion : 5 min


5 min

Homework : 30 min



Reflection/Notes:


Sign: Sign:

Date: Date:



GRADE 10 SUBJECT PHYSICAL SCIENCES WEEK 17 TOPIC ELECTROSTATICS – TIME: 60 MINUTES Lesson 4


LESSON OBJECTIVES

1. Learners will be taught and learn the following concepts: Charges of a particle of an object Charging insulators by contact (tribo-electric charging) 2. The outcomes of the lesson are : At the end of the lesson learners should be able to : Name two particles found in an atom Identify number of protons and electrons in all neutral objects Determine the excess electrons on negatively charged particles and electrons deficiency on a positively charged particles Describe how an insulator may be charged by contact, and the type of charge they acquire


1. Teaching methods Demonstration, Observation, & Question and answer

2. Lesson development: 2.1 Introduction a. Pre-knowledge required. Positive and negative charges Attraction and repulsion forces

b. Baseline assessment Refer to learner activities c. Do corrections on the board explaining and clarifying misconceptions.


Start the lesson with demonstration to make the lesson interesting Rub a plastic ball pen on the dry hair and draw it nearer small pieces of

paper. Ask learner to explain their observation (Only if teaching in the laboratory) Rub a plastic ruler and bring it closer to

thin running tap water. Learners will explain reason for water to bend as it approaches ruler

A balloon is rubbed against dry hair, and brought closer to smooth flowing water. Learners observe and illustrate their observation

Define static electricity and electrification, give examples and explain why it occurs

1. Baseline Activity 1 1.1 What are the charges on a neutral Particle and how do they compare? 1.2 Name the force that exist between unlike charges 1.3 Define an insulator 2.2 Demonstration Activity 2 A learner rubs two substances, plastic and wool together. 2.1 Which particles will move between the plastic and wool?

Baseline: 5 min

Demonstration

30 min

Answering questions

7 min

o Balloon

o Dry hair

o Plastic ruler

o Small pieces of

paper

o Running water from

tap

o Electroscope

o V.d. Graaff

generator



Use electrons and protons to illustrate a neutral atom will have equal number of protons and electrons

Explain that rubbing a neutral object may result in transfer of electrons, leading to an imbalance of protons and electrons, then an object becomes either positively or negatively charged

Using an electroscope, demonstrate how a positively charged Perspex rod, on touching dome of electroscope , swings gold leaves away from each other. (A negatively charged PVC may be used)

Should a V.d.Graaf generator be available, use it to demonstrate how the negatively charged long dry hair strands repel each other

If time allows explain how a photocopier works, how lightning occurs , what should be done and what to avoid during lightning or Spray painting ( better give a guided research task on this section)

Define polarisation and how polarisation occurs 2.3 Conclusion

Summarise the lesson considering shape size and direction of magnetic field lines around the bar magnet and use them to explain position and direction of earth’s poles and the magnetic poles. Illustrate the importance of magnetic field to both people and animals

2.2 Refer to atomic structure to explain why the other particle in an atom does not get transferred between wool and plastic 2.3 Explain why the gold leaf of an electroscope rises when a charged object is brought nearer or touches the dome of electroscope 2.4 Name two variables that can affect the strength of the force between two charged objects 2.5 How can each variable be changed to obtain a stronger force?

Corrections : 8 min

Conclusion: 5 min


5 min

Homework : 30 min



Reflection/Notes:


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Date: Date:



GRADE 10 SUBJECT PHYSICAL SCIENCES WEEK 17 TOPIC CONSERVATION OF CHARGE – TIME: 60 MINUTES Lesson 4


LESSON OBJECTIVES

1. Learners will be taught and learn the following concepts: Principle of conservation of charge Application of principle of conservation of charge 2. The outcomes of the lesson are : At the end of the lesson learners should be able to : State the principle of conservation of charge Calculate the charge after two identical spheres on insulating stands come into contact and separate again Identify that resulting charge on each sphere after contact is the same


1. Teaching methods Demonstration & Question and answer

2. Lesson development: Introduction a. Pre-knowledge required. • Two charges usually acquired by an object • Algebraic sum of the charges b. Baseline assessment •Refer to learner activities c. Do corrections on the board explaining and clarifying misconceptions.


Define an atom as a starting point State the particles an atom is consist of Identify the mass of each particle. ( protons, electrons and neutrons) Allocate the signs +ve and –ve to protons and electrons respectively. Give a

reason why it is scientifically acceptable to allocate those signs in terms of their algebraic sum. Explain that neutrons has no charge

Allocate the charge of 1.60 x10-19 C and give it the symbol e. Explain what makes the charge of an electron and proton differ

Engage learners in discussion to explain when is an object electrically neutral Indicate to learners that the charge of an electron is the smallest amount of

free charge discovered Provide symbol for charge and demonstrate how bigger charges and

number of electrons can be calculated from the equation q = eN where N is an integer

1. Baseline Activity 1 1.1 What are the two charges that an object may acquire? 1.2 When do positive and negative charges develop? 1.3 What type of force will be experienced by two objects carrying like charges? 2.2 Demonstration Activity 2 2.1 State the principle of conservation of charge 2.2 When is the charge quantized? 2.3 How many electrons must be removed from an electrically neutral silver dollar to give it a charge of + 2,4 micro-coulombs?

Baseline: 5 min

Demonstration

35 min

Answering questions

5 min



Explain when is the charge said to be quantized Demonstration example :

How many electrons are there in one coulomb of negative charge? Hint : Learners should always start by recopying the equation from the Data sheet provided in the exam. Teachers should provide learners with copies now It is advisable for the learners to substitute without changing the subject of the formula. q = eN

1.00 = 1.6 x 10-19 x N N = 6,25 x 1018 Therefore there are 6,25 x 1018 electrons in 1 C of charge 2.3 Conclusion

Summarise the lesson explaining the earth as the big magnet. The earth behaves like a bar magnet and has poles. The difference between magnetic of a bar magnet and earth’s magnetic field are explained. Explain the Aurora Borealis and the solar winds. Use common migration in certain season to emphasise ability of animals and flies to navigate using magnetic field

Corrections: 5 min

Conclusion: 5 min


5 min

Homework: 30 min



Reflection/Notes:


Sign: Sign:

Date: Date:



GRADE 10 SUBJECT Physical Sciences WEEK 18 TOPIC Charge quantization – Time 60 minutes Lesson 1


LESSON OBJECTIVES

The outcomes of the lesson are : At the end of the lesson learners should be able to : State the principle of quantization of charge Calculate the charge or number of electrons from the equation q = eN


1. TEACHING METHOD/S USED IN THIS LESSON: Demonstration ; Question and answer method 2. LESSON DEVELOPMENT 2.1 Introduction a) PRE-KNOWLEDGE learners need understanding of the following: i) Pre-knowledge required. Two charges usually acquired by an object An atom and what is consisting an atom Charges on protons and electrons b) BASELINE ASSESSMENT (educator to design a worksheet/ transparency or write questions on the board [preferably a worksheet to save time] to gauge the learners memory of their relevant prior knowledge) [5 min] QUESTIONS for the BASELINE ASSESSMENT 1.1 Write the value of charge of an electron. 1.2 What are the particles consisting an atom? 1.3 What nature is the charge carried by an electron? c) Do corrections and clarify misconceptions 2.2 Main Body (Lesson presentation) [35 min]

Define an atom as a starting point: A atom is the smallest particle of matter that can not be divided into simpler substances State the particles an atom is consist of : protons, electrons and neutrons) Identify the mass of each particle. ( protons, electrons and neutrons) Allocate the signs +ve and –ve to protons and electrons respectively. Give a reason why it is scientifically acceptable to allocate those signs in terms of their algebraic sum -

their algebraic sum is equal to zero. . Explain that neutrons has no charge. It is neither positive nor negative. It is naturally neutral. Allocate the charge of 1.60 x10-19 C and give it the symbol e. Explain what makes the charge of an electron and proton differ. Protons are much bigger compared to electrons. The ratio of electro: proton is approximately 1:1836 Engage learners in discussion to explain when is an object electrically neutral? Indicate to learners that the charge of an electron is the smallest amount of free charge discovered State the quantization of charge: every charge in the universe consists of integer multiples of the electron charge.



Provide symbol for charge and demonstrate how bigger charges and number of electrons can be calculated from the equation q = eN where N is an integer Explain when is the charge said to be quantized Demonstrate how to calculate number of electrons: example :

How many electrons are there in one coulomb of negative charge? Hint : Learners should always start by recopying the equation from the Data sheet provided in the exam. Teachers should provide learners with copies now to start practicing. It is advisable for the learners to substitute without hanging the subject of the formula. q = eN 1.00 = 1.6 x 10-19 x N N = 6,25 x 1018 Therefore there are 6,25 x 1018 electrons in 1 C of charge Learners Activity [ 10 min] 2.1 State the principle of quantization of charge. 2.2 When is the charge quantized? Explain 2.3 Give reason why it is acceptable to allocate + and – on the protons and electrons respectively 2.4 Explain why electrically neutral substances have a charge of zero. .5 How many electrons must be removed from an electrically neutral silver dollar to give it a charge of + 2,4 micro-coulombs?

Corrections [5 min]

3. Conclusion [5 min] Summarise the lesson explaining the earth as the big magnet. The earth behaves like a bar magnet and has poles. The difference between magnetic of a bar magnet and earth’s magnetic field are explained. Explain the Aurora Borealis and the solar winds. Use common migration in certain season to emphasise ability of animals and flies to navigate using magnetic field

HOMEWORK QUESTIONS/ ACTIVITY (educator must give learners a few questions to answer at home by either writing them on the chalkboard or giving an exercise from the prescribed textbook) [30 min]. RESOURCES USED: A4 paper size, Bar magnet, Iron filling, Several compasses Worksheets



Reflection/Notes:


Sign: Sign:

Date: Date:



GRADE 10 SUBJECT PHYSICAL SCIENCES WEEK 18 TOPIC EMF, POTENTIAL DIFFERENCE(PD)

TIME: 60 MINUTES Lesson 2


LESSON OBJECTIVES

1. Learners will be taught and learn the following concepts: emf of a battery Potential difference across terminals of a battery Relationship between emf and potential difference of a battery 2. The outcomes of the lesson are : At the end of the lesson learners should be able to : Define an emf of a battery Define the potential difference across the ends of a conductor Identify the difference between emf and potential difference, and the unit of measurement for both Define the unit of measurement of potential difference (volt)


1. Teaching methods Demonstration & Question and answer

2. Lesson development: 2.1 Introduction a. Pre-knowledge required. Connection of an ammeter in a circuit (in series) Connection of a voltmeter, across a battery, resistor, etc Symbols of components of a circuit b. Baseline assessment Refer to learner activities c. Do corrections on the board explaining and clarifying misconceptions.


To make your lesson more interesting, provide learners with circuit components, mainly those quite relevant to the lesson. e.g. voltmeter, batteries, resistor and a switch.

Learners will record the voltmeter reading for both an open switch and closed switch. (Voltmeter may be connected across a resistor or across a battery depending on time available). Lost volts may be introduced to simplify your explanation

1. Baseline Activity 1 1.1 What is the function of a voltmeter in a circuit? 1.2 How should a voltmeter be connected in circuit? 1.3 In which unit is the potential difference measured? 1.4 What is the energy conversion that

takes place in a battery? 1.5 Why is it that the ammeter can not be

connected across a battery or a resistor in a circuit?

2.2 Demonstration Activity 2 2.1 Define an emf

Baseline: 5 min

Demonstration

30 min

o Light bulbs

o Resistors

o Batteries

o Ammeter

o Voltmeter

o Switch



From the results observed, define the potential difference in terms of potential energy per unit charge between the two points(The potential difference, V, between two points in a circuit is defined as the amount of work done, W, when one coulomb of charge passes from one point to the other point. The SI unit for potential difference is Volt, V

and an emf in terms of maximum potential difference when no current flows Provide a unit for both quantities (volt) and define a volt Potential difference = energy transferred between two points

Charge moving past the two points V = W Q

Calculation demonstration may be done using: What is the potential difference of a light bulb if a charge of 17,5 C pass through it, and radiates 4 200 J of energy? Ask learners to always start by copying the formula from the data sheet

V = W Q

Substitute without changing the subject of the formula

V = 4200 17,5 emphasise mark allocation here

Learners use their calculators (help them) to find the voltage from V = 4200

17,5

An answer without a unit is a wrong answer, practice that from class exercise to tests and assignments etc More questions may be added to activity two

2.3 Conclusion

In conclusion, describe how the voltmeter can be connected in a circuit. Define

emf, potential difference and the volt. Illustrate important calculation steps.

2.2 Calculate the potential difference across the terminals of a battery if a charge of 3 C gains 27 J of energy passing through the battery 2.3 Although potential difference and emf are both measured in volts, they are not the same. Describe the difference between emf and voltage 2.4 2.5

Answering questions

7 min

Corrections: 8 min

Conclusion: 5 min


5 min

Homework: 30 min



Reflection/Notes:


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GRADE 10 SUBJECT PHYSICAL SCIENCES WEEK 18 TOPIC RESISTANCE – TIME: 60 MINUTES Lesson 3


LESSON OBJECTIVES

1. Learners will be taught and learn the following concepts: Current in a circuit Calculations based on I = Q

∆t 2. The outcomes of the lesson are : At the end of the lesson learners should be able to : Define electric current (I) State the unit in which current is measured Calculate the current that flows in a circuit or through certain component State the direction in which the current flows


1. Teaching methods Demonstration , Question and answer

2. Lesson development: 2.1 Introduction a. Pre-knowledge required. Particles of an atom Relationship between current and resistance Conventional current b. Baseline assessment Refer to learner activities

c. Do corrections on the board explaining and clarifying misconceptions.


Provide an ammeter (if possible the large scale that can be seen from any position in class)

Ask learners to explain how ammeter should be

1. Baseline Activity 1 1.1 In which direction does current flow in

a circuit? 1.2 Mention three particles of matter 1.3 Which of the particles mentioned above is responsible for the low of electric current ? 1.4 Describe the relationship between current and resistance in a conductor and potential difference 1.5 How does direction of electric current

differ from direction of flow of electrons?

2.2 Demonstration

Baseline: 5 min

Demonstration: 30 min

Answering questions: 10 min

o Light bulbs

o Resistors

o Batteries

o Ammeter

o Voltmeter

o Switch



connected in a circuit

Describe what the learners should consider if given ammeter to connect in a circuit.

Learners are reminded of what the ammeter measures in a circuit(current)

Use a simple circuit diagram to explain the direction of flow of charges in a circuit as opposed to direction of electric current

Define electric current and write an equation from the definition :

I = Q ∆t

Describe each quantity and provide the unit of measurement for each NB : Please inform learners that it is scientifically unacceptable to use “sec” as unit of time and “amps” for the unit of current Assist learners to convert to SI units. Explain what each letter stands for,

and demonstrate how to reach the required unit. e.g. If current is in amperes

Activity 2 2.1 Define current 2.2 In which SI unit is current measured? Define this SI unit of current 2.3 Describe how should an ammeter be connected in a circuit 2.4 Calculate the current that flows when 100 C of charge pass through an ammeter in 5 seconds 2.5 A current of 10 A flows through a light

bulb for an hour. How much charge flows through this light bulb in an hour?

Corrections: 10 min

Conclusion: 5 min

Homework: 30 min



K H D Ampere (A) d c m x 100 ÷ 10 ÷ 1000 x 1000 x 10 ÷ 100 Introduce micro-, nano-, pico- at this stage and assign a scientific value for each Micro (µ) - x 10-6 Nano (n) - x 10-9 Pico (p) - x 10-12 For calculation purpose learners should follow the following steps: o Re-write equation as it appears on the information sheet o Substitute without changing subject of the formula

2.3 Conclusion

Chalkboard / whiteboard summary concludes the lesson , considering the

definition of current, ampere and correct approach on doing calculations



Reflection/Notes:


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GRADE 10 SUBJECT PHYSICAL SCIENCES WEEK 18 TOPIC VOLTAGE AND CURRENT MEASUREMENT

TIME: 60 MINUTES Lesson 4


LESSON OBJECTIVES

1. Learners will be taught and learn the following concepts: Connection of voltmeter and ammeter in a circuit Recording readings from both the ammeter and voltmeter Draw a circuit diagram 2. The outcomes of the lesson are : At the end of the lesson learners should be able to : Explain the correct connection of both an ammeter and voltmeter Accurately record readings from an ammeter and voltmeter Draw a circuit diagram with correct symbols for given components


1. Teaching methods Demonstration , Investigative & Question and answer

2. Lesson development: 2.1 Introduction a. Pre-knowledge required. Definition of current and potential difference Symbols of components of a circuit

b. Baseline assessment Refer to learner activities c. Do corrections on the board explaining and clarifying misconceptions.


Precaution: Because ammeters are sensitive, and to avoid damage, discuss the connection of ammeter and voltmeter before learners touch the apparatus. i.e. always ensure that the ammeter is connected in series, with the red connected to the side attached to positive of the battery and black connected to negative terminal from the battery starting with the biggest scale. Provide learners with clear instructions to set-up circuit that measures current

through a resistor or light bulb. (If using demonstration method, learners should connect the circuit components themselves)

1. Baseline Activity 1 1.1 What is an electric current? 1.2 Which instrument is used to measure current in a circuit? 1.3 What is the function of a voltmeter? 1.4 Draw the symbols for the following

circuit components : A resistor, bulb, voltmeter, ammeter, a battery etc.

2.2 Demonstration Activity 2 2.1 Define an emf 2.2 Calculate the potential difference across the terminals of a battery if a charge of 3 C gains 27 J of energy passing through the battery

Baseline: 5 min


Answering questions

7 min

o Light bulbs

o Resistors

o Batteries

o Ammeter

o Voltmeter

o Switch



Learners should change the position of an ammeter and record their results Explain why an ammeter can not be connected in parallel with the resistor,

battery or a light bulb Explain how the voltmeter should be connected in a circuit ( in parallel with

resistor, battery etc. because it has higher resistance and no current passes through it)

Allow learners to change the position of the voltmeter from battery to resistor or bulb and record the results

Ask learners to draw a circuit diagram , you can add more components to

the sketches below:

2.3 Conclusion

Refer to the chalkboard/transparency summary, explaining how a voltmeter and

an ammeter should be connected in a circuit. Review symbols and circuit

diagrams for specific circuit.

2.3 Although potential difference and emf are both measured in volts, they are not the same. Describe the difference between emf and voltage 2.4 Explain how the flow of charges differ with the flow of electrons in a circuit 2.5

Corrections: 8 min

Conclusion: 5 min


5 min

Homework: 30 min



Reflection/Notes:


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GRADE 10 SUBJECT PHYSICAL SCIENCES WEEK 19 TOPIC RESISTANCE – TIME: 60 MINUTES Lesson 1


LESSON OBJECTIVES

1. Learners will be taught and learn the following concepts: Resistance and its unit Energy transformation in battery and other circuit components Application of resistors on daily lives 2. The outcomes of the lesson are : At the end of the lesson learners should be able to : Define resistance and ohm Illustrate the microscopic description of resistance in terms of electrons moving through the conductor Explain energy transformation in a battery and resistor



2. Lesson development: 2.1 Introduction a. Pre-knowledge required. Electric current and circuit diagrams Potential difference

b. Baseline assessment Refer to learner activities



Simple demonstration using an ammeter, voltmeter, wires and batteries can make the introduction of the lesson interesting. Connect the ammeter, voltmeter and the batteries together, then ask learners to record the results.

Repeat the same, add the resistor and ask learners to record the results. Learners will compare the results observed without a resistor and the results

observed with a resistor. Seek explanation of the drop in current as in the second observation

1. Baseline Activity 1 1.1 Define resistance 1.2 What is the SI unit of potential

difference? 1.3 Describe the energy conversion

that take place in : a) Radio speaker b) Light bulb c) Electric stove 1.4 Give the difference between emf and potential difference 1.5 Why can’t an ammeter be connected across the battery in a circuit? 2.2 Demonstration Activity 2 2.1 Define resistance

Baseline: 5 min



o Light bulbs

o Resistors

o Batteries

o Ammeter

o Voltmeter

o Switch



Define resistance R as the property of matter that tends to oppose the flow of current in a conductor( If possible, show learners some of the common samples of the resistors)

Define the unit of resistance(ohm) as one volt per ampere and show the ratio V

I Give the microscopic description in terms of electrons moving through the

conductor Identify the factors that influence the resistance of a conductor and explain

how each factor affects the resistance of a metallic conductor ( If time allows, you may demonstrate to the learners. Otherwise summary is enough )

o The longer the conductor, the higher is the resistance o Resistance increase with an increase in Temperature o Thicker conductors have lower resistance than thinner conductors of the

same material o Different materials will have different resistance. Nichrome (alloy of Nickel

and Chromium) will have higher resistance than copper or aluminium Mention application of resistance in daily life, e.g. stove, heaters, geysers,

electric iron, light bulbs, and etc.

The heating effect of current is utilised in the electrical heating appliances such as electric iron, room heaters, water heaters, etc. All these heating appliances contain coils of high resistance wire made of nichrome alloy. When these appliances are connected to power supply by insulated copper wires then a large amount of heat is produced in the heating coils because they have high resistance, but a negligible heat is produced in the connecting wires because the wires have low resistance.

2.2 In which SI unit is resistance measured? Define this SI unit 2.3 State the factors that influence resistance of a metallic conductor 2.4 What is the scientific name given to the ratio V ? I 2.5 A long nichrome wire has more

resistance to current than a short one of the same thickness. Explain why.

Corrections: 10 min

Conclusion: 5 min

Homework: 30 min



The heating effects of electric current is utilized in electric bulbs for producing light. When electric current passes through a thin high resistance tungsten filament of an electric bulb, the filament becomes white hot and emits light.

An 'electric fuse' is an important application of the heating effect of current. When the current drawn in a domestic electric circuit increases beyond a certain value, the fuse wire gets over heated, melts and breaks the circuit. This prevents fire and damage to various electrical appliances.

Explain why a battery in a circuit goes flat eventually by referring to energy transformation that take place in a battery and resistor. i.e. When the potential energy has been converted into other forms of energy and the difference in potential energy between the positive and the negative terminals of the battery is zero, the battery goes flat.

2.3 Conclusion

Chalkboard / whiteboard summary concludes the lesson , considering the

definition of resistance, ohm and the factors influencing resistance of a metallic

conductor. Daily application of resistors should be stated to inform learners of link

between Science in class and daily application (importance of resistors) of

Science.



Reflection/Notes:


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GRADE 10 SUBJECT PHYSICAL SCIENCES WEEK 19 TOPIC RESISTORS IN SERIES 2 – TIME: 60 MINUTES Lesson 3

LESSON SUMMARY FOR: DATE STARTED: 122222 DATE COMPLETED: TTIIMMEE :: 6600 MMIINN

LESSON OBJECTIVES

1. Learners will be taught and learn the following concepts: Effect of resistors in series Total resistance in a circuit Potential difference across each resistor and total potential difference 2. The outcomes of the lesson are : At the end of the lesson learners should be able to : Measure resistance of each resistor and calculate the total resistance of the circuit Measure potential difference across of each resistor and calculate the total potential difference in a circuit Describe the effect of resistors connected in series


1. Teaching methods Demonstration , Investigative & Question and answer 2. Lesson development: 2.1 Introduction a. Pre-knowledge required. Resistance, calculations and current Potential difference




From the previous summary : resistors in series are:

o Potential dividers

o Current is the same

Total resistance increases and the circuit diagram, calculations to find resistance,

current or potential difference can be done using

R = V

I

1. Baseline Activity 1 1.1 Define resistance 1.2 How should ammeter and voltmeter be

connected in a circuit 1.3 What is the relationship between current and resistance in a circuit? 1.3 Measure current on each resistor and record results 1.4 Measure potential difference on each one of the resistors and record the results 2.2 Demonstration Activity 2 2.1 What effect do resistors in series have on the total resistance of the circuit ? 2.2 A circuit consists of a 12 V battery connected across a single resistor. If the current in the circuit is 3 A, calculate the size of the resistor. (4Ω) 2.3 Two 5Ω resistors are connected in series with a 12 V battery. Determine:

Baseline: 5 min


o 3 Resistors

o Batteries

o 3 Ammeters

o 4 Voltmeter

o Switch



Provide learners with a question to demonstrate manner in which calculation(s) should be done in physical science.

Example 1 The current through light bulb in the section of a circuit is 0,625 A whereas the voltmeter reading is 240 V. Calculate the resistance of the light bulb. 2.3 Conclusion

Chalkboard / whiteboard summary concludes the lesson , stating that resistors in

series are:



o Total resistance increases

Report writing skills can be practiced from time to time using demonstrations

available.

(a) the potential difference across each resistor; and (b) the current flowing in the circuit. (6 V, 1.2 A)

2.4 . Consider the following circuit and then answer the questions below.

a. State the potential difference between X and Z.

b. State the potential difference between X and Y.

c. How much potential is left at Y In the circuit below, the reading on the ammeter is 3.2 A.

Answering questions

10 min

Corrections :10 min

Conclusion: 5 min

Homework: 30 min



Determine: a. the reading on the voltmeter; b. the potential difference across the 40 resistor; and

Reflection/Notes:


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GRADE 10 SUBJECT PHYSICAL SCIENCES WEEK 19 TOPIC RESISTORS IN PARALLEL – TIME: 60 MINUTES Lesson 3


LESSON OBJECTIVES

1. Learners will be taught and learn the following concepts: Effect of resistors in parallel Total resistance in a circuit Potential difference across each resistor and total potential difference 2. The outcomes of the lesson are : At the end of the lesson learners should be able to : Measure resistance of each resistor and calculate the total resistance of the circuit Measure potential difference across of each resistor and calculate the total potential difference in a circuit Describe the effect of resistors connected in parallel



2. Lesson development: 2.1 Introduction a. Pre-knowledge required. Resistance, calculations and current Potential difference




Divide learners into groups and provide in each group : 3 Resistors ( e.g. 1Ω, 3Ω, and 5Ω)

Batteries

4 Ammeters

4 Voltmeter

Switch, otherwise a simple class demonstration will do.

1. Baseline Activity 1 1.1 Define resistance 1.2 How should ammeter and voltmeter

be connected in a circuit 1.3 What is the relationship between current and resistance in a circuit? 1.3 Measure current on each resistor and record results 1.4 Measure potential difference on each one of the resistors and record the results 2.2 Demonstration Activity 2 2.1 What effect do resistors in series have on the total resistance of the circuit ? 2.2

Baseline: 5 min

Demonstration

30 min

o 3 Resistors

o Batteries

o 3 Ammeters

o 4 Voltmeter

o Switch



Depending on the time available, learners should be given chance to: write investigative question, hypothesis and identify variables. Assist them to identify dependent, independent and constant variables

Connect three resistors in parallel to each other with the switch and batteries

Connect an ammeter before each of the resistors, and the last ammeter

closer to the batteries then record the current on each ammeter. e.g.

Current divides (branches) in parallel

Draw the circuit diagram on the board and each learner copies it from the board with each of the ammeters marked on the board. e.g. A1, A2, and A3

Connect the voltmeters across each of the resistors and the fourth one should be connected across the batteries

Learners will record the readings on each voltmeter. Total current is calculated from I1, I2, and I3 and the sum is compared to

current in the ammeter closer to the batteries IT = I1 + I2 + I3

2.3 Conclusion


parallel are:

o Current dividers

2.3 2.4 2.5

Answering questions

10 min

Corrections: 10 min

Conclusion: 5 min

Homework: 30 min



o Potential difference is the same

o Total resistance decreases. Effective resistance of resistors in parallel is lower

than the resistance in the smallest resistor


available.

Reflection/Notes:


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GRADE 10 SUBJECT PHYSICAL SCIENCES WEEK 19 TOPIC RESISTORS IN SERIES – TIME: 60 MINUTES Lesson 4


LESSON OBJECTIVES







Main Body (Lesson presentation)

Divide learners into groups and provide in each group : 3 Resistors ( e.g. 1Ω, 3Ω, and 5Ω)

Batteries

4 Ammeters

4 Voltmeter

Switch, otherwise a simple class demonstration will do.

1. Baseline Activity 1 1.1 Define resistance 1.2 How should ammeter and

voltmeter be connected in a circuit

1.3 What is the relationship between current and resistance in a circuit? 1.3 Measure current on each resistor and record results 1.4 Measure potential difference on each one of the resistors and record the results 2.2 Demonstration Activity 2 2.1 What effect do resistors in series have on the total resistance of the circuit ?

Baseline: 5 min



o 3 Resistors

o Batteries

o 3 Ammeters

o 4 Voltmeter

o Switch



Depending on the time available, learners should be given chance to: write investigative question, hypothesis and identify variables. Assist them to identify dependent, independent and constant variables

Connect three resistors in series with the switch and batteries.

e.g. Connect an ammeter before each of the resistors, and the last ammeter

closer to the batteries then record the current on each ammeter. Current is the same throughout the circuit

Draw the circuit diagram on the board and each learner copies it from the board with each of the ammeters marked on the board. e.g. A1, A2, and A3

Connect the voltmeters across each of the resistors and the fourth one should be connected across the batteries

Learners will record the readings on each voltmeter. Total potential difference is calculated from V1, V2, and V3 and the sum is

compared to potential difference across the batteries VT = V1 + V2 + V3

2.3 Conclusion


series are:



o Total resistance increases


available.

Corrections: 10 min

Conclusion: 5 min

Homework: 30 min



Reflection/Notes:


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Date: Date:



GRADE 10 SUBJECT PHYSICAL SCIENCES WEEK 19 TOPIC RESISTORS IN PARALLEL 2 – TIME: 60 MINUTES Lesson 4


LESSON OBJECTIVES








From the previous lesson summary : resistors in PARALLEL are:

o Current dividers

o Potential difference is the same

o Total resistance decreases. Effective resistance of resistors in parallel is lower

than the resistance in the smallest resistor and the circuit diagram, calculations

to find resistance, current or potential difference can be done using

1. Baseline Activity 1 1.1 Define resistance 1.2 How should ammeter and voltmeter

be connected in a circuit 1.3 What is the relationship between current and resistance in a circuit? 1.3 Measure current on each resistor and record results 1.4 Measure potential difference on each one of the resistors and record the results 2.2 Demonstration Activity 2

1. Find the current in the 20Ω and 5Ω resistors in the following circuit.

Baseline: 5 min

Demonstration

30 min

o 3 Resistors

o Batteries

o 3 Ammeters

o 4 Voltmeter

o Switch



R = V

I

Equation for the calculation of the parallel resistances R1 and R2:

Provide learners with a question to demonstrate manner in which calculations should be done in physical science.

Example 1

a) Calculate the effective resistance of the parallel combination b) Determine the potential difference on V2 c) How much is the potential difference through R1? d) Find potential difference across terminals of the battery Insist that learners should identify given quantities, what is required to be

calculated and the relevant equation Transcribe the equation to the board and learners do the same on their books

2. In the circuit below, the reading on the ammeter is 3.2 A.

Determine:

a. the reading on the voltmeter;

b. the potential difference across the 40Ω resistor; and

c. the current in the 40Ω resistor.

Answering questions

10 min

Corrections: 10 min

Conclusion: 5 min

Homework: 30 min



Substitute without changing subject of the formula

Indicate mark allocation and emphasise the importance of the unit

Example 2

Use the diagram below and calculate:

a) total resistance in a circuit

b) current in A1

c) How does current in A1 relate to current in A2 ?

d) Determine V1

e) Where do you think potential difference will be lesser? V1 or V2? Give a reason

2.3 Conclusion

Chalkboard / whiteboard summary concludes the lesson, showing how calculations

can be done in physical sciences. Learners are reminded of importance of

transcribing and substituting without changing subject of the formula

3.

For the circuit above: a. Determine the total resistance. b. Find the reading on the ammeter. c. Draw a voltmeter in the correct place to measure the potential difference across the 0.3Ω resistor. d. Draw an ammeter in the correct place to measure the current in the 0.3Ω resistor. e. Determine the readings on the meters mentioned in parts (c) and (d) above. 4) Explain, step by step, how to calculate the amount of current (I) that will go through each resistor in this parallel circuit, and also the voltage (V) dropped by each resistor:



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