Chemistry

ChemistrySTRUCTURE AND

BONDING IN MATTER

Grade 10 AdvancedUnit 1

Name: ------------------------------------- Class: -----------1

By the end of the chapter, most students know the mass and charge in atoms and ions up to element 56 .Show how the electronic structure explains the patterns of elements in the periodic table and manipulate quantities such as proton number and mass number. They understand ionic, covalent and metallic bonding in terms of bond types. They write balanced molecular and ionic equations for simple reactions. They explain the macro-properties of the different states of matter in terms of their micro-structure.

الفص�ل هذا نهاي�ة معرفةالكتل�ة ف�ي الطالب معظ�م م�ن يتوق�ع ،العنص�ر حت�ى واأليونات الذرات ف�ي الشحن�ة كي�ف 56و الطالب ي�بين ،

الجدول ف��ي العناص��ر أنماط يفس��ر أ��ن االلكترون��ي للتركي��ب يمك��ن . عل�ى يج�ب الكتلي والعدد ال�بروتونات عدد مث�ل كميات يعال�ج و الدوريم�ن المعدني�ة الرواب�ط ، التس�اهمية ، األيوني�ة الرواب�ط يفهموا الطالب . متوازن�ة أيوني�ة و جزيئي�ة معادالت الطالب يكت�ب أ�ن الترابط أنواع حي�ث . المختلف��ة المادة حاالت خص��ائص الطالب يشرح أن بس��يطة لتفاعالت

. الجزيئية أو الصغيرة تراكيبها خالل من

Unit 1

2

17.1 Describe the distribution of mass and charge within an atom and deduce the numbers of protons, neutrons and electrons present in both atoms and ions, given proton and nucleon numbers.

والنيترونات 17.1 البروتونات عدد منها ويستنتج ذرة ضمن الكهربائية والشحنة الكتلة توزيع يصف. والنيكليونات البروتونات عدد يُعطى عندما ، األيونات وفي الذرات في الموجودة وااللكترونات

Objectives Students will be able to:1. Understand that atoms are made up of a nucleus consisting of protons and neutrons surrounded by electrons in specific orbital's or shells.2. Define and use the terms proton number, Nucleon number.3. Describe the distribution of mass and charge within an atom and Deduce the numbers of protons, neutrons and electrons present in both atoms and ions, given proton and nucleon numbers.

Structure and propertiesوالخصائص التركيب

http://www.youtube.com/watch?v=Gsf7jhWr6ng

http://www.youtube.com/watch?v=EP9EtP3gRZo&feature=related

* New Chemistry for you :30-34

Atoms are made up of three different subatomic particles: protons (p), neutrons (n) and electrons (e).The nucleus is at the centre of the atom, and contains the protons and neutrons and the electrons in specific orbital's around the nucleus.

Atomic Number “Proton Number” (Z): Number of protons.

Mass Number “Nucleon Number” (A): Number of protons + Number of neutrons.

3

Key Vocabulary

AtomNucleusProtonNeutronElectronOrbital’s – Shells IonsProton numberNucleon number










ExercisesQ1- Write down the definition of following terms. تعريف اكتب

التالية .المصطلحاتa. The mass number “Nucleon Number” (A) of an atom.

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b. The atomic number “Proton Number”(Z) of an atom.

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c. Protons.

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d. Electrons.

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e. Neutrons.

---------------------------------------------------------------------------------------------------------------------------------------Atom

Atomic number Proton

Number (Z)

Mass number Nucleon

Number (A)

Number of electrons

Number of protons

Number of neutrons

24 Mg 12

8O 16

Q2- Complete the following table. . أكملالتالي الجدول

Q3- Explain why atom is electrically neutral?؟ كهربائيا متعادلة الذرة تعتبر لماذا

Neutral

متعادل

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--------------------------------------------------------------------------------

4

http://sonalismrules.files.wordpress.com/2008/03/ist2_2697517_positive_negative_handshake.jpg

Electronic configuration اإللكتروني التوزيع

17.2 Deduce the atomic structure of an atom or ion of any given element up to barium (56) and show how the structures explain the pattern of elements in the periodic table.

العنصر على يستدل 17.2 عنصرماحتى لذرةأوأيون الذري كيف 56التركيب وهوعنصرالباريوم،ويبين ،. الدوري الجدول العناصرفي يفسرأنماط اإللكتروني التركيب أن

Objectives :

1. Deduce the atomic structure of an atom or ion of any given element up to barium (56) and show how the structures.

2. Explain the pattern of elements in the periodic table.

Key vocabulary:

Atomic structureElementsPeriodic table.Electron configuration

http://www.youtube.com/watch?v=EP9EtP3gRZo

http://www.mikeblaber.org/oldwine/chm1045/notes/Struct/EConfig/IMG00006.GIF

* New Chemistry for you :32 and 60

Electron configuration shows the number of electrons in each Orbital.Number of electrons in the outer shell gives the number of Group.

المجموعة رقم على يدل العنصر لذرة الخارجي المدار في اإللكترونات عددNumber of shells give the number of period in the periodic table.

الدوري الجدول في الدورة رفم على يدل الذرة فى المدارات عدد

The table below explains shells and number of electrons.

Shell Electrons number First 2Second 8Third 8

Example 1: 1224Mg Example 2 : 8

16O

Group: ( 2 )Period:( 3 )

Group: ( )Period: ( ) 5











ExercisesQ1: Draw the electronic configuration of the following atoms and determine period and group number.

الدورة و المجموعة رقم وحدد الجدول في للعناصر االلكتروني التوزيع :ارسم

Element Electronic Configuration Period Number Group Number

5B

13Al

9F

19K

2He

6

Ionsاأليونات

In an atom the number of Protons = the number of electrons, So The atom is electrically neutral

In an ion: The number of positively charged protons ≠ number of negatively charged electrons.Each atom try to attains the stable electronic configuration as a noble gases

An ion is electrically charged atom

http://www.youtube.com/watch?v=dHZlMbBZ0UA

* New Chemistry for you 85

Look at the diagrams below which present ions formation states

Ion أيون

Atom ذرة

Lose electrons Gain electrons

7






Writing activity

Use the above diagram to write a short story between sodium and chlorine.

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Support student’s English language by doing this activity.

http://www.youtube.com/watch?v=QqjcCvzWwww&feature=PlayList&p=C9D5927352BA3C33&playnext_from=PL&playnext=1&index=4

http://www.youtube.com/watch?v=xTx_DWboEVs&feature=related

8
















Q1- Calculate the number of electrons, protons and neutrons in the following:

Exercises

9

Relative isotopic mass, relative atomic mass.النسبية , الذرية الكتلة النسبية النظائرية الكتلة

17.3 Define the terms relative isotopic mass, relative atomic mass, relative molecular mass and relative formula mass based on the carbon-12 scale and be able to calculate the relative molecular mass of a compound, given its formula and a relative atomic mass table.

17.3 “ ” “ النسبية ” والكتلة ، النسبية الذرية الكتلة ، النسبية النظائرية الكتلة مثل مص�طلحات يعرفالكربون - مقياس على بناء عندما. 12للجزئ ما، لمركب النسبية الجزيئية الكتلة حساب من ويتمكن

النسبية الذرية للكتل جدول ولدية بصيغته علم يكون

Objectives 1. Define the terms relative isotopic mass, relative atomic mass.2. Define relative molecular mass and relative formula mass based on the carbon-12 scale.3. Calculate the relative molecular mass of a compound, given its formula and a relative atomic mass table.

Key vocabulary:-Relative isotopic mass

-Relative atomic mass.

-Relative molecular mass

Relative formula Mass and relative molecular mass The relative formula mass of a substance (or molecular mass Mr ) Is the sum of the relative atomic masses of the atoms present in a formula unit or molecule.

Relative formula massRelative molecular massRelative molecular mass

Hint;The relative formula mass or molecular mass given as Mr

10

http://www.onlinemathlearning.com/molecular-mass.html

http://www.absorblearning.com/chemistry/demo/units/LR304.html#Calculatingrelativeatomicmasses

*New Chemistry for you 36-37







http://www.absorblearning.com/chemistry/demo/units/LR304.html










ExercisesQ1: What is the meaning of the term relative formula mass (R.F.M)?

Q2- Use the following table to calculate the relative formula mass (R.F.M) or molecular mass for each of the following:

Name Symbol Atomic Number R.A.M

Aluminum Al 13 27

Chlorine Cl 17 35.5Nitrogen N 7 14Oxygen O 8 16Sodium Na 11 23

c) Aluminum Oxide Al2O3

11

b) Sodium chloride NaCla) Nitrogen dioxide NO2

Spectrometry and isotopesوالنظائر الطيف قياس

17.4 Know that mass spectrometry can furnish information on relative isotopic masses and isotopic abundance.

النسبية 17.4 النظائریة الكتل عن یوفرمعلومات أن یمكن الكتلي الطيف تحليل� أن یعرفوالكثرةالنسبيةللنظائر

17.5 Know that isotopes can be distinguished by their different numbers of neutrons and explain why the relative atomic mass of many elements is not a whole number.

لماذا 17.5 فيهاویشرح الموجودة للنيترونات المختلفة األعداد خالل تمييزالنظائرمن باإلمكان أنه یعرف. صحيحة أعداد من العناصرغيرمكونة من للعدید النسبية الذریة الكتلة

Objectives:1. Describe the mass spectrometer.2. Explain how mass spectrometry can give information about masses and abundance of isotopes. 3. Relate the difference in isotopes to the different numbers of neutrons.4. Explain why the relative atomic mass of many elements is not a whole number.

Key Vocabulary MassSpectrometerIsotopicAbundance

A- العينة تبخيرB- التأين غرفةC- األيونات تسريعD- المجالالمغناطيسيE- المراقبة(monitor) F- التفريغ مضخة إلى

) يعرف ) األيونات الشحنة موجبة األجسام كتل لدراسة جهاز طور الكتلة لقد ويمثل بمطيافمخططا هذه ًالشكل من الكثرة. لواحد و كتلتها حسب األيونات فصل في وأهميته األجهزة

للنظائر النسبية

Let students watch a short animation / video clip to help them to appreciate how a mass spectrometer works.

The mass spectrometer: is a device that separate particles based on their mass. The samples must move through the following steps1-vaporization- heat the substance to turn it into gas2- Ionization – to form positive ions.3- Acceleration – to move the ions fast by an electric field.4- Deflection - by magnetic field where ions are separated according to their mass.5-detection-where a monitor displays graph of different ions according to their mass and abundance audio visual resource.

12

http://www2.chemistry.msu.edu/faculty/reusch/VirtTxtJml/Spectrpy/MassSpec/ma

sspec1.htm

*New Chemistry for you: 364-6







Isotopesالنظائر

Isotopes are atoms differ in mass because they differ in the number of neutrons.The relative atomic mass of many elements is not a whole number because of the presence of isotopes. The average relative atomic mass is the weighted average for all isotopes of a given element based upon their relative percent abundance.

. النظائر النيترونات بعدد تختلف ألنها الذرية الكتلة في تختلف ذرات هيالنسبية الذرية و الكتلة العناصر لتلك نظائر وجود بسبب الحقيقي العدد ليست العناصر من لعدد�

الم النسبة على بناء المكونة النظائر لج�ميع النسبي الوزن هو النسبية الذرية الكتلة وية ئمعدللتواجدها.

http://www.colorado.edu/physics/2000/isotopes/index.html

* New Chemistry for you:35

Example

Chlorine exist as two naturally occurring isotopes Cl-35 and Cl-37 . if the Cl-35 has an abundance of 75.76% and Cl-37 has abundance of 24.24% ,determine the relative atomic mass of chlorine.

Solution: Ar =

= 35.48

13






ي .1 كما العنصر من عينة في ونسبها الذرية كتلها نظائر ثالثة لعنصر أن الكتلة مطياف بواسطة ليوجد :

النسبية ا الذرية المئوية لكتلة النسبة

27.977 92.21% 28.971 4.70% 29.974 3.09%

. العنصر؟ اسم وما للعنصر الذرية الكتلة احسب

Exercises

14

Bonding الروابط

17.6 describe ionic and covalent bonding.17.6 . ) والرابطةالتساهمية ) التكافؤالكهربائي ارتباط الرابطةاألیونية یصف

Objectives:1. Relate types of bonding between atoms to its electron configuration.2- Show the role of valence electrons in determining the type of bonds between atoms.3- Represent ionic and covalent bonds using Lewis structures

Key Vocabulary

Electron configurationValence electronsIonic bondsCovalent bondsLewis structures

15

chemical bond ( الكيميائية ( الرابطة is a force of attraction between the atoms which holds them together.

The atoms combine with one another to reach a noble gas electronic configuration and become stable and this is why atoms banded together.

Octet rule ( يةالثمان قاعدة )

When atoms combine to form a chemical bond, they gain, lose or share electrons in such a way that each atom gets noble gas configuration or 8 electrons in its outer most shell (or 2 electrons in the outer most K shell.)

Lewis electron dot structure ( لويس ( تركيبshows the symbols of elements along with their valence electrons as dots around them.

http://www.youtube.com/watch?v=QqjcCvzWwww

http://www.youtube.com/watch?v=yjge1WdCFPs

http://www.youtube.com/watch?v=WXyFMJ0eJA0&feature=related

Valence (outer most) electrons are usually the only electrons used in chemical bonds. So, only valence electrons are shown in electron dot structure. As you are familiar that all of the group 1 elements have 1 valence electron so they are shown with 1 dot. Group 2 elements have 2 dots; group 3 elements have 3 dots and so on.

Li • • Be • •

• B • •

• C ••

•

: N ••

•

: O •..

. .

: F •..

. .

: Ne :..











16

IONIC BONDاأليونية الرابطة

An ionic bond is formed when a metal atom gives its valence electrons to a non metal atom. By losing electrons, the metal forms a positively charged ion (cation). The non- metal atom gains electrons and forms negatively charged ion (anion).The positively and negatively charged ions attract one another. The strong force of attraction between the oppositely charged ions is called ionic bond.

ذرة تفقد عندما األيونية الرابطة لذرة الفلزتتكون وتعطيها الخ�ارجية الالفلزإلكتروناتها ( ) ( ) ويحدث أنيون سالبة شحنة الالفلز ذرة وعلى كاتبون موجبة شحنة الفلز� ذرة على وتتكون

بين القوي الكهربي التج�اذب هذا و والسالبة الموجبة األيونات بين الكهربي التج�اذباأليونية بالرابطة يسمى .األيونات

Example of ionic bond formation between Na and Cl

. ..Na + . Cl :

2,8,1 2,8,7

Na+ + :C :l-

2,8 2,8,8

Examples of ionic bond formation in CaF2 and K2 S

http://www.youtube.com/watch?v=CGA8sRwqIFg&NR=1&feature=fvwp


* New Chemistry for you: 248-250












17

Exercises

Q1: Try for ionic bond formation in the following elements:

1. Al and Br

2. Mg and N

3. Mg and O

18

Covalent bondingالتساهمية الرابطة

The chemical bond formed by the sharing of electrons between atoms of non-metals is known as a covalent bond. The sharing of electrons takes place in such a way that each atom in the resulting molecule gets the stable noble gas electronic configuration. The electron pair which is shared makes a covalent bond. Covalent bonds are of three types- single, double and triple covalent bonds.

التي الكتروناتها ت الرابطة في اللالفلزات ذرات لمشاركة نتيجة تكون . الى التساهمية الرابطة تنقسم التساهمية بالرابطة تعرف الخارجية

, وثالثية ثنائية أحادية أنواع ثالث

a) Single covalent bond( اآلحادية التساهمية ( الرابطة

A single covalent bond is formed by the sharing of one pair of electrons between two atoms:

1) formation of hydrogen molecule

2) Formation of Fluorine molecule

3) Formation of Hydrogen bromide molecule

http://www.yksd.com/distanceedcourses/Courses09/PhysicalScience/Lessons/SecondQuarter/Chapter05/05-02/30CovalentBonds.gif

http://ibchem.com/IB/ibfiles/bonding/bon_img/cov3.gif













19

b) Double covalent bond( الثنائية التساهمية ( الرابطة

A double covalent bond is formed by sharing 2 pairs or 4 electrons between the two atoms

Formation of oxygen molecule

A triple covalent is formed by sharing 3 pairs or 6 electrons between the two atoms

Formation of nitrogen molecule

c) Triple covalent bond ( الثالثية التساهمية ( الرابطة

في ( ) استعمل الترابط لبيان وخطوط نقاط من رسومات لویس أشكال: المختلفة المركبات عددمن

في: الرابطةاألیونية ً و فمثال والرابطة – في لوریدالصودیوم أكسيدالمغنيسيوم. الميثان وفي األمونيا في التساهمية

الترابط . تكافؤلبيان إلكترونات باستخدام ً وحّضرعرضا صّمم.بإمكانك الكيميائية الروابط لدرس التالية المراجع استخدم

Activity

Resources used in the section of chemical bonding 1) New chemistry for You ( LawrieRyan ) page 35-36 and page 248-2622) http://www.youtube.com?v=yMQrDAqvqhs&NR=13)http://en.wikipedia.org/wiki/Chemical_bond#Overview_of_main_types_of_chemical_bonds4) http://chemactive.com/flash_spring/ib/atomic_structure_ppt_2009.swf

http://www.youtube.com/?v=yMQrDAqvqhs&NR=1

http://en.wikipedia.org/wiki/Chemical_bond

http://en.wikipedia.org/wiki/Chemical_bond

http://chemactive.com/flash_spring/ib/atomic_structure_ppt_2009.swf

20

Metallic bondingالفلزية الرابطة

17.7 Explain metallic bonding in terms of a lattice of positive ions surrounded by a sea of mobile electrons and explain the physical properties of metals and alloys in terms of this bonding.

المتحركة، 17.7 اإللكترونات من بسحابة المحاطة الموجبة األيونات من شبكة بداللة الفلزية الرابطة يفسرالفيزيائية األرتباط ويفسرالخصائص هذا بداللة والسبائك للفلزات

Objectives:1. Explain metallic bonding.

2. Explain the physical properties of alloys.

3. Write an example of alloy.

Key vocabulary:

metallic bondingdrift DelocalizedAlloy

Each of magnesium atom gives up its electrons from its outer shell into the “sea” Or “ cloud” of electrons. The electrons can drift about in the metal. We call them ‘delocalized ’ electrons.

delocalized means "not fixed in one place" or "free to move".

http://www.ausetute.com.au/metallic.html

http://www.ausetute.com.au/metallic.html.

*New Chemistry for you: 268

المغنيسيوم من ذرة غالفه تفقدكل من وتتحول الخارجي االكتروناتأو بحر " الى االلكترونات" من الذرة سحابة الكترونات نسميها. حول

متمركزة .غير

متمركزة الكترونات " ”تعني غير أو" واحد مكان في ثابتة لها ليستالتحرك حرية







21

Exercises

Q1: Mention the properties of metals:

1( 2(

3( 4(

5( 6(

Q2: Why metals are good conductors of electricity?

…………………………………………………………………………………………………………….….. …………………………………………………………………………………………………….………….…

Q3- Compare between ionic and metallic bonding:

22

http://en.wikipedia.org/wiki/Metal

http://www.lcc.ukf.net/chem/metaluses.htm

http://www.creative-chemistry.org.uk/gcse/documents/Module5/N-m05-14.pdf

*New Chemistry for you: 270- 272

Alloyالسبائك

An alloy is a mixture of metals.المعادن: السبائك من خليط

Aeroplanes are made from aluminium alloysPure iron metal Carbon add in to pure iron metal

) Alloy (

Q1: Write three examples of alloys:a) ………………

b) ……………..

c) ……………..

Q2: State why alloys are widely used in industry:……………………………………………………….

………………………………………………………..









23

Giant Covalent Moleculesالعمالقة الجزيئات

17.8 Know that some covalent compounds, such as the element carbon and the compound silicon(IV) oxide, form giant molecular structures.

السيليكون (17.8 أكسيد ومركب الكربون عنصر مثل الترابط التساهمية المركبات بعض أن تكون) IVيعرف . ضخمة جزيئية تراكيب

Objectives:

1. Identify the giant covalent molecular.

Key vocabulary:

- giant covalent compoundsQ1:The following figures represents giant molecular structurea) write the name of each structure using the word in below box

b) Answer the questions below: 1) Which giant molecule is formed from two elements?

…………………………………………………………………………………………………..

2) Mention these two elements ?

………………………………………………………………………………………………….

3) Which giant molecules are made of one element only?

………………………….. …………………………………………………………………… 4) Mention that element? ……………………………………………………………………………………………….

http://www.chemguide.co.uk/atoms/structures/giantcov.html

*New Chemistry for you: 258

Diamond , Graphite , Fullerene , Silica

……………………… ……................…….

a b

c d

……………………… ……................…….







17.9 Show an understanding of allotropy.

17.9( الكيميائي ( الترآيب وتماثل الشكل اختالف التآصل معنى .یفهم

Allotropy التآصل

Allotropes: are different forms of the same element ( in the same state).

( الحالة: ( نفس في العنصر لنفس مختلفة أشكال التآصلQ1- The following figures represents allotropes of carbon , write the name of each structure:

…………………. …..……………

Q2- Fill in the table below with the Physical properties of diamond and graphite, using New chemistry for you 258-259

Point of comparison Diamond Graphite

Hardness

Type of bonding

Melting point

Electric conductivity

http://www.ausetute.com.au/allotropy.html

http://en.wikipedia.org/wiki/Allotropy

Objectives:

1. Define allotropy

2. Explain the physical properties of some allotropy

Key vocabulary:

Allotropy

24









25

Properties Covalent and ionic compoundsواأليونية التساهمية المركبات خصائص

17.10 Explain the differing physical properties of covalent and ionic compounds in terms of their bonding and be able to deduce the type of bond from information about physical properties.

لمركب 17.10 المختلفة الفيزیائية الخصائص روابطها ات یشرح بداللة وأیونية االستدالل تساهمية من على ویستطيع االرتباط نوعالمركبات لهذه الفيزیائية الخصائص حول المعلومات

Objectives:

1.Explain the differing physical properties of covalent and ionic compounds.2. Deduce the type of bond from information about physical properties.

Key vocabulary:metalsnon-metalsIonicCovalent Metallic

The bonding and structure of a substance explain its properties; the table below summarizes this relation so that you can compare the different types of structure and bonding:

BondingIonic

(Between metals and non-metals)

Covalent (between non-metals)

Metallic(between metals)

Structure Giant ionic Giant covalent Simple molecular

Giant metallic

Melting point high high low high

Conduct electricity

Not when solid, but they do when molten

or dissolved in water.

(when ions are free)

No/except graphite

noYes

(has free electrons)

Example

Sodium chloride Diamond Water Zinc

26

Exercises

Q1: Study the table below then answer the following questions:

The properties of substances A, B, C, D, E and F are given below.

a) Which substances have a giant ionic structure? ....................

b) Which substances have a simple molecular structure? ....................

c) Which substances have a metallic structure? ....................

d) Which substances have a giant molecular structure? ....................

e) Which substances are liquids at room temperature (25oC)? ....................

f) Which substances are gases at room temperature (25oC)? ....................

g) Which two substances are most likely to dissolve in an organic solvent? ................

Substance Melting point 0C Boiling point 0CElectrical

conductivity when its solid

Electrical conductivity

when its liquid or molten

A 651 1100 Good GoodB 790 1250 Poor GoodC 5 80 Poor PoorD 803 1430 Poor GoodE -138 0 Poor PoorF 3500 ? Poor Poor

http://hyperphysics.phy-astr.gsu.edu/hbase/chemical/bond2.html

http://antoine.frostburg.edu/chem/senese/101/compounds/ionicvscovalent.shtml

http://hyperphysics.phy-astr.gsu.edu/hbase/chemical/bond2.html

http://antoine.frostburg.edu/chem/senese/101/compounds/ionicvscovalent.shtml

27

Ionic compoundsاأليونية المركبات

17.11 Explain why molten ionic compounds and solutions of ionic compounds conduct electricity.

17.11 . الكهرباء توصل األیونية المركبات ومحاليل المنصهرة األیونية لماذاالمركبات یشرح

Objectives :

1. Molten ionic compounds conduct electricity.

2. Solutions of ionic compounds conduct electricity.

3. Solid ionic compounds can’t conduct electricity.

Key vocabulary:

-Molten ionic compounds

Ionic compounds made up of ions (charged particles) .Solid sodium chloride contain fixed ions can’t move to the electrodes. So, it can’t conduct electricity.

However, when they are melted or dissolved in water, the ions become free to move around. So, it can conduct electricity.

Write another paragraph for sodium chloride

Writing activity

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Lab activity

1. Set up the circuit as shown2. Dip the electrodes into some solid sodium chloride.

- Did the solid conduct the current?……………………………………..

3. Now half-fill the beaker with water, and stir.- Does the blub light up now?……………………………………..

- Does the solution conduct electricity?………………………………………

4. Switch off your power pack as soon as the test is completed.

Q1) Why do the solutions of ionic compound conduct electricity?

Q2) Explain: molten potassium bromide conduct electricity?

http://www.chem.iastate.edu/group/Greenbowe/sections/projectfolder/flashfiles/electroChem/conductivity.html

* New Chemistry for you: 252










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Writing chemical equationsالكيميائية المعادالت كتابة

17.12 Write equations with state symbols for simple reactions, including ionic equations for reactions in aqueous solution, given the formulae of reactants and products.

لتفاعالت 17.12 المادة حالة على تدل الرموزالتي على تحتوي معادالت یكتبصيَغ یعرف ،عندما مائي مح�لول في تحصل لتفاعالت أیونية معادالت فيها ،بما بسيطة

. ونواتجها المتفاعلة الموادObjectives :

Write equations with state symbols for simple reactions

Key vocabulary:

- symbols- reactions- ionic equations- aqueous solution- Reactants- products

What is a chemical equation? ؟ الكيميائية المعادلة ماهي

When a chemical reaction occurs, it can be described by an equation. This shows the chemicals that react (called the reactants) on the left-hand side, and the chemicals that they produce (called the products) on the right-hand side .Unlike mathematical equations, the two sides are separated by an arrow, that indicates that the reactants form the products and not the other way round.

How to write the chemical equations? المعادلة تكتب كيف الكيميائية

بالشروط التقيد يجب الرمزية المعادلة ولكتابة رمزية أو لفظية تكون قد المعادلةالعناصر , للمادة الكيميائي الرمز لكتابة ثنائية الالزمة جزيئات شكل في تكتب الغازية

H2 , N2, O2 .الكيميائية بصيغها فتكتب المركبات مثل. MgO, NaClاما الصلبة العناصرالمفردة ذراتها تكتب والكربون المعادلة . Mg, Na, Cالفلزات موازنة تتم ذلك بعد

. الناتجة الذرات عدد تساوي المتفاعلة الذرات عدد تكون بحيثChemicals can be represented by their names or by their chemical symbols. Symbols of element gases are diatomic like H2 , N2, O2 . Solid elements can be represented by simples like Mg, Na, C, Al. Compounds are represented by their chemical formula like MgO, NaCl.For metals with different oxidation states ,add Roman number when represented by their names e.g Copper(II) oxide (CuO)There are reversible reactions, which means that the reactants react together to form the products, but as soon as the products are formed, they start to react together to reform the reactants! Reversible reactions are indicated with a double arrow as shown in the example below:

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رم تكتب وضوحا أكثر المعادلة صغيرة ولتكون زالمادة حاالت عن تعبر

To make a chemical equation complete, the state of matter of each substance should also be included. This indicates whether the substance is:

(s) solid(l) liquid(g) gas

(aq) aqueous (dissolved in water)

* In this example, solid magnesium ribbon burns in oxygen gas to form solid magnesium oxide:

2 Mg (s) + O2 (g) -- 2 MgO (s)

http://www.youtube.com/watch?v=YDJFfZ5WqZQ&feature=PlayList&p=C9832A956597F2C3&playnext=1&playnext_from=PL&index=65


Student activity (1):

Use your periodic table and table of poly atomic ions to write the chemical formulas for the following compounds.

Show the following steps;

Step one - Write the symbols for the elements or the polyatomic ions in the compound.

Step two - Look up the valence numbers of the elements or the polyatomic ions involved and write them as superscripts to the right of the elemental symbols.

Step three - Use the correct combination of ions (and the polyatomic ions) to produce a compound with a net charge of zero. Multiple ions are indicated with subscripts.

Teacher will be provide periodic table to students with a table of polyatomic ions










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Q1) Write the correct chemical formulas for the following:

1. Lithium oxide 2. Potassium chloride

3. Calcium oxide

4. Barium bromide

5.Lead(IV) carbonate

6. Copper(II) nitrate

7. Iron(III) oxide

8. Tin(IV) fluoride

9.lead(II) carbonate

10. copper(I) sulfate

Exercises

التأكسد حاالت متعددة . الفلزات االتينيه باألرقام التأكسد رقم يكتبمثال:

Iron(II) oxide FeO

Iron(III) oxide Fe2 O3

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a) Hydrogen reacting with nitrogen to produce ammonia gas.

b) Silver nitrate solution reacting with hydrochloric acid to give sliver chloride and nitric acid

c) The decomposition of hydrogen peroxide give water and oxygen

d) The reaction of carbon monoxide with iron(III) oxide to give iron and carbon dioxide. This reaction occurs at high temperatures in the blast furnace.

HomeworkWrite word and formula equations for the chemical reaction that occur when aqueous solution of sodium hydroxide is added to hydrochloric acid to give sodium chloride and water.

Q2) Write full balanced equations, including state symbols, for the following reactions:

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Kinetic particle theory

17.13 Use the kinetic particle theory to explain the main characteristics of the three states of matter and changes between the states:•the basic assumptions of the kinetic theory as applied to an ideal gas;•the liquid state, including melting, vaporisation and vapour pressure;•the lattice structure of a crystalline solid.

الثالث المادة لحاالت الرئيسية لتفسيرالخصائص الجزیئية الحركة نظریة یستخدم17.13األخص: بينها،وعلى فيما والتغيّرات

غازمثالي؛ على فيتطبيقها الجزیئية الحركة لنظریة األساسية االفتراضات•والتبخروالضغطالبخاري: االنصهار فيها بما الحالةالسائلة•صلبة. بلوریة لمادة الشبكي التركيب•

Objectives :

1. Know the basic assumptions of the kinetic theory as applied to an ideal gas. 2. Use the kinetic particle theory to explain the main characteristics of the three states of matter and changes between the states.

Key vocabulary:- kinetic particle theory- ideal gas- lattice structure- crystalline solid- vaporisation

a) Basic assumptions of the kinetic theory:1. A gas has no fixed shape or volume, but always spreads out to fill any container.2. There are almost no forces of attraction between the particles so they are completely free of each other.3. The particles are widely spaced and scattered at random throughout the container so there is no order in the system.4. The particles move rapidly in all directions, frequently colliding with each other and the side of the container.5. With increase in temperature, the particles move faster as they gain kinetic energy.

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Gases have a very low density (‘light’) because the particles are so spaced out in the container (density = mass / volume).Density order: solid > liquid >>> gasesGases flow freely because there are no effective forces of attraction between the gaseous particles - molecules.Ease of flow order: gases > liquids >>> solids (no real flow in solid unless you powder it!)Because of this gases and liquids are described as fluids.Gases have no surface, and no fixed shape or volume, and because of lack of particle attraction, they always spread out and fill any container (so gas volume = container volume).Gases are readily compressed because of the ‘empty’ space between the particles.Ease of compression order: gases >>> liquids > solids (almost impossible to compress a solid)

Gas pressureWhen a gas is confined in a container the particles will cause and exert a gas pressure which is measured in atmospheres (atm) or Pascals (Pa = N/m2) - pressure is force/area on which force is exerted.The gas pressure is caused by the force created by millions of impacts of the tiny individual gas particles on the sides of a container.For example - if the number of gaseous particles in a container is doubled, the gas pressure is doubled because doubling the number of molecules doubles the number of impacts on the side of the container so the total impact force per unit area is also doubled.This doubling of the particle impacts doubling the pressure is pictured in the two diagrams below.

Using the particle model to explain the properties of a Gas

2 x particles===>P x 2

http://www.docbrown.info/page03/3_52states.htm













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Exercises

Q1) Draw simple diagrams to show the three states of matter?

Solid particles Liquid particles Gas particles

Q2) Use assumptions of the kinetic theory and the shapes of the three states of matter to complete the following table:

Property Solids Liquids GasesOrder of particles

الجسيمات ترتيبKinetic energy

الحركية الطاقةIntermolecular forces

الجزيئات بين التجاذب قوةShape الشكل

Spacing of particlesالجسيمات بين المسافة

Compressibilityالضغظ على القدرة

Conduction of heat الحرارة توصيل

Q3) Which of the three states of matter:a. Have the most ordered molecules--------------b. Take the shape of the container.---------------c. Have very weak forces between its molecules--------------.d. Have fixed shape.--------------e. Have the higher kinetic energy molecules.--------------f. Have higher compressibility.------------------------

Chemistry

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