Law of Conservation of Mass

Chemical Reactions

Chemical Reactions Objectives1.Classify and name compounds in chemical reactions2.Describe chemical reactions in word and chemical

equations.3.Balance chemical equations based on the Law of

Conservation of Mass.4.Identify and classify types of chemical reactions

and energy changes involved.5.Predict products and energy changes in a chemical

reaction. 6.Identify and test factors that affect the rate of

chemical reactions.

Chemical ReactionsDue:• Law of Conservation Mass Lab

Objectives: • I can convert word equations into chemical

equations. (Chemical Nomenclature)• I can validate the Law of Conservation of Mass

through inquiry lab.

Chemical Bonding Exam Analysis

• How did you prepare for this exam?

• How long (days/hrs.) did you spend studying for this exam?

• What concepts were challenging on the exam?

• Why were these concepts challenging to you?

Chemical Bonding Exam Analysis

• How did you prepare for this exam?

• How long (days/hrs.) did you spend studying for this exam?

• What concepts were challenging on the exam?

• Why were these concepts challenging to you?

Law of Conservation of Mass Lab• Purpose: To prove the Law of Conservation of Mass• Establish a hypothesis: Will an open or closed

system best validate the Conservation of Mass Lab? Explain your answer.

• Materials: Determine what materials you will use for each experiment.

• Procedures: Establish procedures for each experiment (closed expt. vs open expt.)

Open vs. Closed System

http://www.chem.umass.edu/people/botch/Chem122S08/Chapters/Ch6/InternalE.html

Chemical Reactions: 3.10Infinite Campus Update:• Chemical Bonding Exam • Chemical Bonding Review-Gallery Walk• Chemical Bonding:Open Response Question• Molecular Structures TableDue:• Law of Conservation Mass Lab

Objectives: • I can convert word equations into chemical equations. (Chemical

Nomenclature)• I can validate the Law of Conservation of Mass through inquiry

lab.

Chemical Reactions: 3.10

Objectives: • Address Chemical Bonding Exam • I can convert word equations into chemical

equations. (Chemical Nomenclature Review).• I can balance chemical equations.

Infinite Campus Check-Up

• Assess infinite campus and record any missing or incomplete assignments.

• Discuss how you plan on making up any missing assignments. (RTI/GSH, ESS)

• Record current average.• Signature of student and parent• Due: Wednesday, March 12th.

Chemical ReactionIron chemically reacts with Oxygen to produce Iron(II) Oxide

a. Convert word equation to chemical equation.b. Determine if the equation is balanced by assessing

how many atoms there are for each element on the reactant’s side and the product’s side.

Balancing Chemical EquationsWhy? Observe the Law of Conservation of Mass

Rules: 1. Add coefficients in front of substances, do NOT

change subscripts.

2. First balance elements that only appear once on each side of the equation.

3. Make sure coefficients are expressed in lowest terms.

Chemical Reactions: 3.10.14

Homework:• Complete Word Equations Worksheet(front/back)• Complete Infinite Campus Update Assignment

Chemical Reactions: 3.11Overdue Reminder:Law of Conservation of Matter Data/Analysis

Objectives: • Address Chemical Bonding Exam • I can convert word equations into chemical

equations. (Chemical Nomenclature Review).• I can balance chemical equations.

Word Equation 2014 Worksheet

2. Aluminum bromide reacts with chlorine to yield aluminum chloride and bromine.

Word Equation 2014 Worksheet

Chemical Reactions

Homework:• Balancing Chemical Equation Worksheets.• Review for Chemical Bonding Makeup Exam-Fri.

Chemical Reactions: 3.12Due:• Infinite Campus Update Assignment• Word Equation 2014 worksheet(front/back)Objectives: • I can balance chemical equations.• Address Chemical Bonding Exam• Address Law of Conservation of Mass Lab

Balancing Chemical Equations

Word Equations and Balancing

Chemical Bonding Exam

Chemical Reactions: 3.13Due:• Infinite Campus Update Assignment(over-due)• Balancing Reaction Worksheets

Objectives: • I can balance chemical equations.• I can classify chemical reactions

Homework:• Review chemical bonding content-Makeup Fri.

Chemical Compounds Venn Diagram

Ionic Compounds Covalent Compounds

Similarities

Chemical Bonding Exam

• Make-up exam this Friday (3.14)• Could earn up to five points to initial exam score.• Required for students who made lower than a B

on exam. • Take advantage of RTI or ESS prior to Friday

Balancing Chemical Equations

• Review homework using gallery walk.

Chemical Reactions: 12.10

Objectives: • I can balance and classify chemical reactions• Complete Chemical Reaction Lab• Review for Chemical Bonding and Reactions

Balance and Classify Chemical Equations

Just need to check and see if they are balanced. 1. Mg + O2 ------> MgO

2. Mg + HCl ----> MgCl2 + H2

3. (NH4)2(CO3) -----> NH3 + CO2 + H2O

4. Ca(CO3) + HCl ----> CaCl2 + H2O + CO2

5. Zn + CuCl2 ----> ZnCl2 + Cu

6. CuCl2 + Na3(PO4) ---> Cu3(PO4)2 + NaCl

7. HCl + Na(OH) ----> H2O + NaCl

8. C2H6O + O2 -----> CO2 + H2O

Classifying Chemical Reactions

There are five main types of chemical reactions:1.Synthesis2.Decomposition3.Single Replacement4.Double Replacement5.Combustion•Try to classify the reactions as one of those five. •You can use textbook or internet to help you.

Law of Conservation of Mass Lab H2O + Na(HCO3) ----> CO2 + Na(OH) + H2O

Purpose: Use your data to validate whether an open or closed experiment would best prove the Law of Conservation of Mass.

Open vs. Closed System

http://www.chem.umass.edu/people/botch/Chem122S08/Chapters/Ch6/InternalE.html

Law of Conservation of Mass Lab H2O + Na(HCO3) ----> CO2 + Na(OH) + H2O

Purpose: Use your data to validate whether an open or closed experiment would best prove the Law of Conservation of Mass.

Homework(Due Monday)• Complete bulleted questions under the following

headings:Background- Conclusion• Separate each section with these headings.

Classifying Chemical Reactions

Chemical Reactions: 3.17Infinite Campus Update:• Chemical Bonding Make-up Exam(posted tonight)• Chemical Bonding Worksheet 2014 (posted tonight)Due:• Law of Conservation of Mass Lab-Rough Draft• Classifying Chemical Reactions TableHomework:• Classification of Reactions• Chemical Reactions Lab-read and complete pre-lab

questions

Classifying Chemical Reactions

There are five main types of chemical reactions:1.Synthesis2.Decomposition3.Single Replacement4.Double Replacement5.Combustion•Try to classify the reactions as one of those five. •You can use textbook or internet to help you.

Chemical Reactions: 3.24

Due:• Predicting Products Worksheet Objectives:• I can balance and classify chemical reactions.• I can predict the products in a chemical reaction.

Homework:• Complete predicting products worksheet• Check infinite campus-grades post Tues. night

Balancing and Classifying Quiz

Types of Chemical Reactions

1. Synthesis (R+ S ----> RS)2. Decomposition (RS------> R+ S)3. Single Replacement (T+ RS ---> TS + R)4. Double Replacement (R+S- + T+U- ---> R+U-+ T+S-)5. Combustion (CxHx + O2 ----> CO2 + H2O)

6. Neutralization (Acid + Base--> H2O + Salt)

(type of double replacement reaction)

Chemical Reaction LabReaction Chemical Equation

1

2

3

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5

6

7

8

Chemical Equations to Lab

Just need to check and see if they are balanced. 1. Mg + O2 ------>

2. Mg + HCl ----> 3. (NH4)2(CO3) -----> NH3 + CO2 + H2O

4. Ca(CO3) + HCl ----> CaCl2 + H2O + CO2

5. Zn + CuCl2 ---->

6. CuCl2 + Na3(PO4) --->

7. HCl + Na(OH) ----> 8. C2H6O + O2 ----->

Chemical Reactions: 3.27Over Due:• Chemical Reactions Lab • Due:• Predicting Product worksheetObjectives:• I can classify, predict products, and balance chemical

reactions. • I can predict if a single replacement reaction will

occur in nature. • Check infinite campus-grades post Tues. night

Predicting Products Worksheet

Single Replacement Reactions

• Do all single replacement reactions occur spontaneously?

Predicting Single Replacement Reactions• An Activity Series can help us predict if a single

replacement reaction will take place.

Activity Series Lab Hypothesis CuCl2(aq)Copper (II) chloride

Ag(NO3) (aq)Silver nitrate

HCl (aq)Hydrochloric acid

dH(OH) (l)(d)deionized water

Copper (s)

Magnesium (s)

Zinc (s)

Calcium (s)

Activity Series Lab Hypothesis

• Write out the reactants for each single replacement reaction.• Using the activity series table determine which reactions will occur

spontaneously. • If occur, predict products and balance reactions.

CuCl2(aq)Copper (II) chloride

Ag(NO3) (aq)Silver nitrate

HCl (aq)Hydrochloric acid

dH(OH) (l)(d)deionized water

Copper (s)

Magnesium (s)

Zinc (s)

Calcium (s)

Predicting Single Replacement Reactions• An Activity Series can help us predict if a single

replacement reaction will take place.

Predicting Single Replacement Reactions1. Determine which single replacement reactions below

can occur using your Activity Series diagram:a. K + MgCl2

b. Al + Li3(PO4)

c. Sn2+ + HCl

d. Ag + HCl

e. Pb4+ + H2(SO3)

Thermochemistry

Energy changes that occur during a physical and chemical changes.

Exothermic Reaction

• Energy absorbed by system < Energy released. • The chemical reaction becomes cooler and its

surroundings gets warmer. • Energy is on the product side.• Synthesis and Combustion reactions

• C8H18 + O2 -------> CO2 + H2O + energy

Endothermic Reactions• Energy absorbed by system > Energy released• Chemical reaction gets warmer and its

surroundings gets cooler. • Energy is on the reactant side.• Decomposition ReactionsEx. Photosynthesis

Chemical Reaction Energy DiagramExplain using data from graph whether or not this is an endothermic or exothermic reaction.

Chemical Reaction Energy Diagram

a

Activation Energy

Explain using data from the graph whether is an endothermic or exothermic reaction.

Bell Ringer: Classifying ReactionsClassify and balance each reaction below. Identify

if each reaction is endothermic or exothermic.• H2O + energy ---> H2 + O2

• C4H10 + O2 ----> CO2 + H2O + energy

3. Cl2 + KBr ------> KCl + Br2 + energy

4. K + F2 ---> KF + energy

5. Li(OH) + H2(SO4) ----> Li2(SO4) + H2O

Chemical Reactions Rates• Reaction Rates = how fast the reactants

chemically change into the products. • Collision Theory: Reactant particles will form

products when reactants collide:- at the right position.- and exchange the right amount of kinetic energy.

Rates of Chemical Reactions

• What are factors that can affect the speed of a reaction?

Rates of Chemical Reactions

• What are factors that can affect the rates of reactions?

• Temperature• Concentration of Reactants• Surface Area of Reactants• Catalysts• Inhibitors

Temperature of Reaction

What if we increase the temperature of a reaction?

What if we decrease the temperature of a reaction?

Concentration

• Increase concentration of reactants?

• Decrease concentration of reactants?

Surface Area

• Increase surface area of reactants?

• Decrease surface area of reactants?

Catalysts

• Catalysts speed up reactions, but they are not apart of the chemical reaction.

Ex. Enzymes keep your body temperature around 37oC (98 oF) by speeding up important biological reactions.

Catalyst and Energy Change

Inhibitors

• Inhibitors slow down a chemical reaction.• Inhibitors bind to a catalyst and prevent it

from speeding up a reaction. Ex. Preservation of food. Antioxidants prevent

foods from becoming stale or moldy.