Chemical Reactions

Chemical Reactions Study Guide

• Chpt. 9.4 Acids and Bases

• Chpt. 11: Balancing, Classifying, and Predicting Chemical Reactions

• Chpt. 18.1: Reaction Rates

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 Reaction Pre-Test1. What is a chemical reaction?2. If matter is conserved during a chemical reaction, how is

it new matter is “created”?3. Complete the questions below on the following word

equation:Iron chemically reacts with Oxygen to produce Iron(II) Oxidea. Express the word equation as a chemical equation. b. Give an example of a reactant and a product from this

reaction. c. Balance the chemical equation if needed. d. Circle the type of chemical reaction you think this

represents.: synthesis, decomposition, replacement, neutralization,

combustion

Chemical Reaction

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

Chemical Reactions

What is a chemical reaction? • Use your background knowledge to explain

what a chemical reaction is.• Think about chemical changes you have

observed in your surroundings.• Think about chemical changes on an atomic

level.

Pre-AP Chemistry (2/14)Due: • Acid Rain Article w/qts.• Ingredients Assignment for partial creditObjectives: • Acid/Base Nomenclature Quiz• Balance Chemical EquationsHomework:• Balancing Chemical Equations worksheet (Do even problems on front and back.)

Chemical Reactions• Substances chemically interact to form different

substances. • A substance can be an element or a compound.

• Chemical bonds are broken and created.

Example: Iron chemically reacts with Oxygen to produce Iron(II) Oxide

Chemical Equations Fe + O2 ------> FeO

Reactants:

• Starting substances.• Chemically interact with one another.• Usually located to the left of the arrow.Products:• Ending substances.• Substances formed from the chemical reaction.• Usually located to the right of the arrow.

Chemical Equations Fe(s) + O2 (g) ------> FeO (s)

Abbreviations for state of matter in an equation.• (s)= substance in solid state• (g)= substance in gaseous state• (l)= substance in liquid state• (aq)= substance dissovled in water. (aqueous solution)

Chemical Reactions Fe(s) + O2 (g) ------> FeO (s)

• Are atoms destroyed or created during a chemical reaction?

• No, they are just rearranged to produce new substances.

Chemical ReactionsInfinite Campus Update:• Acid/Base Nomenclature Quiz (15pts.)• Cu and Zn Alloy Lab(10pts.)• Ingredients Assignment (20 pts.)• Acid Nomenclature worksheet (10pts.)

Objectives: • Establish and balance chemical equations

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.

Balancing Chemical Equations a. K + MgCl2 ---------> KCl + Mg

b. Ag2O ---------> Ag + O2

c. CH4 + O2 -------> CO2 + H2O

Chemical Reactions (2/19)

Objectives:• Balance chemical equations• Validate the Law of Conservation of Mass

Chemical Equations

Balancing Chemical Equations

Dihydrogen monoxide + sodium (hydrogen carbonate) ---> carbon dioxide + sodium hydroxide + dihydrogen monoxide

a. convert to chemical equationb. Balance equation if needed.

Law of Conservation Of Mass

• Matter is not created or destroyed.

• Matter is just rearranged.(mass of reactants = mass of products)

That is why it is important to balance chemical equations.

Law of Conservation of Mass Inquiry Lab

• Purpose: To prove mass is conserved in chemical reactions.

• Materials and Procedures: Groups will establish

• Record and analyze data

• Establish a conclusion

Open vs. Closed System

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

pre-AP Chemistry (2/20)

Objectives: • Clarify misconceptions with writing and

balancing chemical equations.

• Validate the Law of Conservation of Mass (Design, perform, and analyze chemical reaction

between Alka Seltzer and tap water).

States of Matter Abbreviations Fe(s) + O2 (g) ------> FeO (s)

Abbreviations for state of matter in an equation.• (s)= substance in solid state• (g)= substance in gaseous state• (l)= substance in liquid state• (aq)= substance dissovled in water. (aqueous solution)

Chemical Equations1. magnesium chloride + fluorine yields magnesium

fluoride + chlorine

2. iron + sulfuric acid yield iron(II)sulfate + sulfur dioxide + dihydrogen monoxide

Pre-AP Chemistry (2/21)Reminder:• Quiz tomorrow over writing and balancing

chemical equations. (complete extra practice problems from paper or webpage)

Objective: • Validate the Law of Conservation of Mass (Design, perform, and analyze chemical reaction

between Alka Seltzer and tap water).

Pre-AP Chemistry (2/25)Reminder:• Quiz over balancing chemical equations.

Objective: • Validate the Law of Conservation of Mass (Design, perform, and analyze chemical reaction

between Alka Seltzer and tap water).

• Formal Lab report due on March 6th(typed)

Chemical Equations1. magnesium chloride + fluorine yields magnesium

fluoride + chlorine

2. iron + sulfuric acid yield iron(II)sulfate + sulfur dioxide + dihydrogen monoxide

Law of Conservation of Mass Inquiry Lab

• Purpose ,Background, Hypothesis: completed

Objectives: • List materials needed for each experiment.• List procedures specific enough for someone else to

repeat. (sign-off by Ms. Leeper)• Perform experiments and record data. (record all qualitative and quantiative data)

Open vs. Closed System

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

Chemical Reactions Bell Ringer1. N2 (g) + H2(g) --------> NH3(g)

a. What is the chemical name of one of the reactants?

b. What is the chemical name of the product?

c. What state of matter is all the substances in this reaction?

d. Balance the chemical equation if needed.

Law of Conservation of Mass Lab

Team # Open System Closed System

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Pre-AP Chemistry (2/27)

Objectives: • Discuss lab results and format of lab report• Discuss types of reactions.• Classify chemical reactions. • Review balancing equations quiz

Homework: • Balancing and classifying chemical reactions

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 Reactions Objectives1. Identify and classify types of chemical reactions.

2. Identify energy changes involved with chemical reactions.

3. Predict products and energy changes in a chemical reaction.

Synthesis (Combination) Reaction

• 2 or more substances chemically combine to form a single substance.

• R+ S ----> RS + energy

• Energy released into surroundings is more than energy absorbed by the system.

( Energy of surroundings > Energy of system)

Decomposition Reaction

• A compound breaks down into simpler substances.

• RS + energy ----> R + S

• Energy of system > Energy of surroundingsWhy? Breaking more bonds then creating bonds.

Single Replacement Reaction

• An element replaces another element in a compound.

• T+ RS ---> TS + R energy

• Usually energy of surroundings > energy of system

Double Replacement Reaction

• Exchange of cations between two compounds. • R+S- + T+U- ---> R+U-+ T+S- + energy

• Usually energy of surrounding > energy of system

Combustion Reaction

• Fuel (hydrocarbons) reacts with oxygen to produce predictable substances and energy.

• CxHx(Ox) + O2 ----> CO2 + H2O + ENERGY

• Energy of Surroundings > Energy of System

Neutralization • An acid and a base react to produce predictable

products. • Changes the pH to 7 (neutral).

Acid + Base -------> H2O + Salt

Salt: The cation comes from the base and the anion from the acid.

Ex. Na(OH) + HCl NaCl + H2O

Pre-AP Chemistry (2/28)Objectives: • Balance and classify chemical reactions.• Classify chemical reactions as either exothermic or

endothermic. • Clarify format of lab report.

Homework: • Work on Formal Lab Report • Chemical Reactions Lab: Read background/procedures and

answer pre-lab qts.

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

Classifying and Balancing Chemical Equations

Pre-AP Chemistry (3/4)Infinite Campus:• Classifying and Balancing Chemical Equations(10pt)

Objectives: • Chemical Reaction Lab

Homework: (Due Wed.)• Conservation of Mass Lab Report –rough draft • Predict products and balance each chemical reaction.

Pre-AP Chemistry (3/6)Infinite Campus:• Classifying and Balancing Chemical Equations(10pt) Due: • Conservation of Mass Lab Report –rough draftObjectives: • Complete chemical reaction lab• Predict products and balance each chemical equation.Homework: (Due Monday)• Complete the lab (balance each equation) • Predict products worksheet

Chemical Reaction Lab

Purpose: • Determine reactants and predict type of rxtn. • Perform, observe, and record chemical reactions.• Predict products and balance each chemical rxtn.

Chemical Equations to LabReaction Chemical Equation

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Pre-AP chemistry (3/11)Reminder: • Rough draft: Conservation of Mass Lab report (partial credit)Objectives: • Predict products and balance chemical equations. • Establish conclusion from chemical reaction lab.Homework:• Predict products and balance reactions worksheet• Conclusion from Chemical Reaction Lab

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 Equations to Lab

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

2. Mg + HCl ----> MgCl + 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

ConclusionA summary that includes the following: • Identify and explain the types of reactions obsvd. ?

• Based on the data section explain which reactions were exothermic and endothermic.

• Which reaction(s) did you like the best and why?

• What did you learn from this lab? (be specific)

Pre-AP Chemistry (3/12)Due:• Chemical Reaction LabObjectives: • Predict products in a chemical reaction.• Predict when single replacement reactions will

occur using the activity series table. Homework:• Complete the Predicting Products worksheet• Read about activity series table and complete

pre-lab questions for Activity Series lab.

Predicting Products

Pre-AP Chemistry (3/13)Infinite Campus Update:• Chemical Reaction Lab (26pts.)

Objectives:• Classifying, predicting products, and balancing

chemical reactions.Homework:• Read procedures for Activity Series Lab• Establish hypothesis for Activity Series Lab

Predicting Products Assessment

Gallery Walk: Predicting Products

At each station complete the following:a. Write the chemical formula of the reactant(s)b.Predict type of reaction c. Predict productsd.Balance chemical reaction if needed

Pre-AP Chemistry (3/14)Infinite Campus:• Chemical Reaction Lab • Law of Conservation of Mass Lab rough draft• Predicting Products worksheet (4th qtr.)Objectives: • Perform and record data from Activity Series Lab• Establish a conclusion (compare data with your

hypothesis)Homework: • Complete post-lab questions

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) Ag(NO3) (aq) HCl (aq) dH(OH) (l)

Copper (s)

Magnesium (s)

Zinc (s)

Calcium (s)

Pre-AP Chemistry 3/18)Infinite Campus Update:• Activity Series Lab• Chemical Reaction Quiz

Objectives:• Predict single replacement reactions using activity

series table.• Predict solubility of products in double replacement

reaction.• Go over chemical reaction quizHomework:Complete Solubility Rules worksheet (due Tues.)Work on Study GuideTest (Friday, March 22nd)

Pre-AP Chemistry 3/19)Infinite Campus Update:• Activity Series Lab• Chemical Reaction Quiz Objectives:• Predict single replacement reactions using activity

series table.• Predict solubility of products in double replacement

reaction.• Go over chemical reaction quizHomework:Work on Study GuideTest (Friday, March 22nd)

Pre-AP Chemsistry (3/20)

Solubility Rules for Ionic Compounds

myweb.bloomu.edu

Ag, Ca, Hg(II)

Predicting Products Using Solubility Rules

Ag(NO3) CaCl2

Na(OH)

Na3(PO4)

NaCl

1. Predict products for each double replacement reaction.2. Determine if one of the products will be a precipitate . 3. Balance the equation if needed.

Predicting Products in a Chemical Reaction Predict the products and balance the equation if needed.

a. Ca + N2 --------> ?

b. Cu2S -------> ?

c. AlBr3 + F2 ------> ?

d. CH4 + O2 -----> ?

e. Ca(OH)2 + H3(PO4) ----->

Predicting Products in a Chemical Reaction

a. 3Ca + N2 --------> Ca3N2

b. Cu2S -------> 2Cu + S

c. 2AlBr3 + 3F2 ------> 2AlF3 + 3Br2

d. CH4 + 2O2 -----> CO2 + 2H2O

e. 3Ca(OH)2 + 2H3(PO4) -----> Ca3(PO4)2 + 6H2O

Chemical Reaction Review1. What are the coefficients that will balance the

chemical equation below? AlCl3 + Na(OH) ----> Al(OH)3 + NaCl

a. 1,3,1,3b. 3,1,3,1c. 1,1,1,3d. 1,3,3,12. What type of chemical reaction is in question 1?

3. Predict the product and balance if needed: Ba (s) + O2 (g) ---------->

Activity Series Lab

• Complete conclusion

• Complete Post Lab Questions

Activity Series Lab1. Using the Activity Series Table, predict whether

the following single replacement reactions would occur:

a. Li + MgCl

b. Hg + Na3P

c. Pb + HF

Chemical Reactions Study Guide

• Chpt. 9.4 Acids and Bases

• Chpt. 11: Balancing, Classifying, and Predicting Chemical Reactions

• Chpt. 18.1: Reaction Rates

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 • Study of energy changes during a reaction.

Energy Review Qts:• When observing a chemical reaction what is the

difference between the system and its surroundings?

• Energy always flows from ____ matter to _____ matter. (cold, hot)

ThermochemistryEnergy changes that occur within reactions.

Endothermic Reactions Exothermic Reactions

Exothermic Reaction• Energy (H) absorbed < Energy (H) released. • The chemical reaction becomes cooler and its surroundings gets

warmer. • Test tube gets? • Energy is on the products side.• Examples: • combustion of fossil fuels (transportation)C8H18 + O2 -------> CO2 + H2O + energy

• cellular respiration in living organisms C6H12O6 + O2 ------> CO2 + H2O + energy

Endothermic Reactions• Energy (H) absorbed > Energy (H) released• Chemical reaction gets warmer and its

surroundings gets cooler. • Test tube gets ?• Energy is on the reactants side.Ex. Photosynthesis

Energy Diagram

(H)

(time)

Chemical Reaction Energy Diagram•Activation Energy (Ea): The minimum amount of energy needed for the reaction to occur.

H: Energy change between reactants and products. ( H = H products – H reactants)

Chemical Reaction Energy Diagram

Does this represent an endothermic or exothermic reaction?

Energy Diagram H reactant > H product Small activiation energy More energy will be released in this reaction

(H)

(time)

Energy Diagram

Activation Energy

Does this represent an endothermic or exothermic reaction?

(H)

(time)

Endothermic Energy Diagram

Activation Energy

• H reactant < H product•Large activation energy•More energy will be absorbed in this reaction

Pre-AP Chemistry (3/21)Infinite Campus Update:• Solubility Rules Homework (10pts.)Objectives: • Interpret energy changes in chemical reactions.• Identify and test factors that affect the rate of

chemical reactions.• Go over quizHomework: • Work on study guide. • Test Friday or Monday?

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? Increase speed of reaction

What if we decrease the temperature of a reaction? Decrease speed of reaction

Concentration

• Increase concentration of reactants?Increases speed of reaction

• Decrease concentration of reactants? Decreases speed of reaction

Surface Area

• Increase surface area of reactants?Increases the speed of a reaction

• Decrease surface area of reactants?Decreases speed of reaction

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.

Chemical Reactions Study Guide

• Chpt. 9.4 Acids and Bases

• Chpt. 11: Balancing, Classifying, and Predicting Chemical Reactions

• Chpt. 18.1: Reaction Rates

Chemical Reaction Study Guide