Chemical Reactions - Warren County Schools

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Chemical Reactions

Chemistry (2/25)

• Acid/Base Quiz

• Interpreting and Balancing chemical equations

Due:

• Acid/Base Nomenclature worksheet for partial credit

Chemical Reactions Objectives

1.Classify and name compounds in chemical reactions

2.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.

Chemistry (2/26)

Infinite Campus Update:

• Acid/Base Nomenclature Worksheet (10pts.)

• Acid/Base Quiz (15pts.)

*Check infinite a lot of missing assignments!*

Objectives:

• Interpreting and Balancing chemical equations

Homework:

• Check for missing assignments on infinite campus

• Balancing chemical equations worksheet

Chemical Reaction Pre-Test

1. 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:

Fe(s) + O

2

(g) ----> FeO (s) a. Give an example of a reactant from this reaction.

b. Give an example of 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 Reactions

• Substances chemically interact to form different substances.

• A substance can be an element or a compound.

Chemical bonds are broken and created.

Example: Fe(s) + O

2

(g) ----> FeO (s)

Chemical Equations

Fe + O

2

------> 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)

+ O

2 (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)

Law of Conservation of Mass

Fe

(s)

+ O

2 (g)

------> FeO

(s)

Are atoms destroyed or created during a chemical reaction?

No, they are just rearranged to produce new substances.

Law of Conservation of Mass

Fe

(s)

+ O

2 (g)

------> FeO

(s)

Balancing Chemical Equations

Why? 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.

Chemistry (2/27)

Objectives:

• Interpreting and Balancing chemical equations

• Review acid/base quiz

Homework:

• Balancing equations worksheet(due Thursday)

• Law of Conservation of Mass pre-lab qts. and hypothesis

• Review acids/bases nomenclature

• Check for missing assignments in infinite campus

Lab:

Law of Conservation of Mass Lab: (Thursday)

Law of Conservation of Mass Lab

Homework:

• Read through the background and procedures section.

• Complete pre-lab questions and hypothesis.

Balancing Chemical Equations

a. K + MgCl

2

---------> KCl + Mg b. Ag

2

O ---------> Ag + O

2 c. CH

4

+ O

2

-------> CO

2

+ H

2

O

Chemical Equations

Chemistry (2/28)

Objectives:

• Interpreting and Balancing Chemical Equations

• Validate the Law of Conservation of Mass with scientific evidence.

Due Today:

• Balancing chemical equations worksheet (turn in tray)

• Law of Conservation of Mass pre-lab qts. and hypothesis

Homework:

• Balancing Chemical Equations practice problems (Fri.)

• Check for missing assignments in infinite campus

Balancing Chemical Equations

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

Law of Conservation of Mass Lab

Purpose:

Validate the Law of Conservation of Mass

Lab Reminders:

• Follow ALL lab procedures carefully.

• Use the same balance for all measurements.

Acid/Base Nomenclature Quiz

Exit Slip:

Interpret and Balance Chemical Equations

1. Cl

2

(g) + KBr (aq) ----> KCl (aq) + Br

2

(l) a. Balance the equation if needed

2. CH

4

(g) + O

2

(g)  CO

2

(g) + H

2

O(g) a. Balance the equation if needed.

b. Identify the diatomic molecule in this reaction.

Exit Slip:

1. Cl

Interpret and Balance Chemical Equations

2

(g) + KBr (aq) ----> KCl (aq) + Br

2

(l) a. Which reactant is a molecule?

b. What is the chemical name of the product that is an ionic compound?

c. What does (aq) mean?

d. Balance the equation if needed

2. CH

4

(g) + O

2

(g)  CO

2

(g) + H

2

O(g) a. Balance the equation if needed.

b. Identify the diatomic molecule in this reaction.

Balancing Chemical Equations

Dihydrogen monoxide + sodium (bicarbonate) ---> carbon dioxide + sodium hydroxide + dihydrogen monoxide a. convert to chemical equation b. 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)

+ O

2 (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 Equations

1. 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 (2/22)

Reminder:

• Quiz today 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).

Chemical Equations

Chemical Equations

1. 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 Ringer

1. N

2

(g) + H

2

(g) --------> NH

3

(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.

Balancing Chemical Equations

Types of Chemical Reactions

1. Synthesis (A+ B ----> AB)

2. Decomposition (AB------> A + B)

3. Single Replacement (A+ BC ---> B + AC)

4. Double Replacement (AB + CD ---> CB + AD)

5. Combustion (C x

H x

+ O

2

----> CO

2

+ H

2

O)

6. Neutralization (Acid + Base--> H

2

O + Salt)

*Each letter represents a substance*

Chemical Reactions Objectives

1. 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.

• A + B ---> AB + 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.

• AB + energy ----> A + B

• Energy of system > Energy of surroundings

Why?

Single Replacement Reaction

• An element replaces another element in a compound.

• A + BC --------> B + A C + energy

• Energy of surroundings > Energy of system

Double Replacement Reaction

• Exchange of cations between two compounds.

• A B + C D + energy ----> C B + A D + more energy

• Energy of Surrounding > Energy of System

Combustion Reaction

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

• C x

H x

+ O

2

----> CO

2

+ H

2

O + ENERGY

• Energy of Surroundings > Energy of System

Neutralization

• Acid and Base react to produce predictable products.

• Changes the pH to 7 (neutral).

Acid + Base -------> H

2

O + Salt

Salt: An ionic compound.

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

Class Reminders:

• Acid Rain Article (15pts.)

• Balance Chemical Equations Worksheet (10pts.)

(balance and classify equations)

• Word Equation Worksheet (10pts.)

*3 rd Quarter Ends: March 8 th*

Chemical Reaction Lab

Purpose:

• Perform and observe types of chemical reactions.

• Determine reactants and predict products.

• Classify chemical reactions.

• Balance chemical reactions.

• Write a formal lab report

3

4

1

2

5

6

7

8

Chemical Equations to Lab

Reaction Chemical Equation

Types of Chemical Reactions

1. Synthesis (A+ B ----> AB)

2. Decomposition (AB------> A + B)

3. Single Replacement (A+ BC ---> B + AC)

4. Double Replacement (AB + CD ---> CB + AD)

5. Combustion (C x

H x

+ O

2

----> CO

2

+ H

2

O)

6. Neutralization (Acid + Base--> H

2

O + Salt)

Chemical Equations to Lab

Just need to check and see if they are balanced.

1. Mg + O

2

------>

2. Mg + HCl ---->

3. (NH

4

)

2

(CO

3

) -----> NH

3

4. Ca(CO

3

) + HCl ----> CaCl

2

+ CO

2

+ H

2

+ H

2

O

O + CO

2

5. Zn + CuCl

2

6. CuCl

2

+ Na

3

---->

(PO

4

) --->

7. HCl + Na(OH) ----> H

2

O + NaCl

8. C

2

H

6

O + O

2

----->

Chemical Reaction Review

1. What are the coefficients that will balance the chemical equation below?

AlCl

3 a. 1,3,1,3

+ Na(OH) ----> Al(OH)

3

+ NaCl b. 3,1,3,1 c. 1,1,1,3 d. 1,3,3,1

2. What type of chemical reaction is in question 1?

3. Predict the product and balance if needed:

Ba (s) + O

2

(g) ---------->

Balancing and Classifying Chemical Reactions

Chemical Equations to Lab

Just need to check and see if they are balanced.

1. Mg + O

2

------> MgO

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

2

3. (NH

4

)

4. Ca(CO

2

3

(CO

3

) -----> NH

3

) + HCl ----> CaCl

2

+ CO

2

+ H

2

O

+ H

2

O + CO

2

5. Zn + CuCl

2

6. CuCl

2

+ Na

3

----> ZnCl

2

+ Cu

(PO

4

) ---> Cu

3

(PO

4

)

2

+ NaCl

7. HCl + Na(OH) ----> H

2

O + NaCl

8. C

2

H

6

O + O

2

-----> CO

2

+ H

2

O

Conclusion

Needs to include the following:

• Identify and explain the types of reactions obsvd. ?

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

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

• What did you learn from this lab?

Infinite Campus Update

• Chemical Reaction Lab (20pts.)

• Balancing Chemical Equation Wksht.(10pts.)

Chemical Reaction Review

1. Classify the type or reaction and balance if needed: a. C

6

H

12

+ O

2

---------> CO

2

+ H

2

O b. LiCl ------> Li + Cl

2 c. H

2

(SO

3

) + Al(OH)

3

-------> H

2

O + Al

2

(SO

3

)

3

Predicting Products in a Chemical Reaction a. Ca + N

2

--------> ?

b. Cu

2

S -------> ?

c. NaBr + F

2

------> ?

d.CH

4

+ O

2

----->

Balancing and Classifying Equations Quiz

Types of Chemical Reactions

1. Synthesis

2. Decomposition

3. Single Replacement

4. Double Replacement

5. Combustion

6. Neutralization

Predicting Products

• Check my webpage for correct chemical formulas prior to balancing.

Predicting Single Replacement Reactions

• An Activity Series can help us predict if a single replacement reaction will take place.

Copper (s)

Magnesium (s)

Activity Series Lab Hypothesis

CuCl

2

(aq) Ag(NO

3

) HCl (aq) dH(OH) (l)

Zinc (s)

Calcium (s)

Activity Series Lab

• Complete conclusion

• Complete Post Lab Questions

Activity Series Lab

1. Using the Activity Series Table, predict whether the following single replacement reactions would occur: a. Li + MgCl b. Hg + Na

3

P 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 Reactions

1. Determine which single replacement reactions below can occur using your Activity Series diagram: a. K + MgCl

2 b. Al + Li

3

(PO

4

) c.

Sn 2+ + HCl d.

Ag + HCl e. Pb 4+ + H

2

(SO

3

)

Chemical Reaction Study Guide Changes

1. Vocabulary words: Thermochemistry

10. HgO + energy ------> Hg + O2

11. Fe + F

2

12. CH

4

+ O

2

----------> FeF

3

---------> CO

2

+ energy

+ H

2

O + energy

15. K(OH) + H

3

(PO4) ------->

18.

Omit last word equation. 

Chemical Reaction Review

1. What are the coefficients that will balance the chemical equation below?

AlCl

3 a. 1,3,1,3

+ Na(OH) ----> Al(OH)

3

+ NaCl b. 3,1,3,1 c. 1,1,1,3 d. 1,3,3,1

2. What type of chemical reaction is in question 1?

3. Predict the product and balance if needed:

BaS + Mg ---------->

Thermo chemistry

Energy changes that occur within reactions.

Endothermic Reactions Exothermic Reactions

Exothermic Reaction

• Energy absorbed < Energy released.

• The chemical reaction becomes cooler and its surroundings gets warmer.

• Energy is on the product side.

• C

8

H

18

+ O

2

-------> CO

2

+ H

2

O + energy

Endothermic Reactions

• Energy absorbed > Energy released

• Chemical reaction gets warmer and its surroundings gets cooler.

• Energy is on the reactant side.

Ex. Photosynthesis

Chemical Reaction Review

1. Using the Activity Series diagram would the following reactions take place?

a. Al + Cu(OH) b. Ag + HCl

2. Classify the type or reaction and balance if needed: a. C

6

H

12

+ O

2

---------> CO

2 b. LiCl ------> Li + Cl

2 c. H

2

(SO

3

) + Al(OH)

3

+ H

2

O

-------> H

2

O + Al

2

(SO

3

)

3

Endo

thermic vs.

Exo

thermic

Infinite Campus Update

• Chemical Reaction Lab(20pts.)

• Activity Series Lab (10pts.) (1,2,4,6)

• Balancing Chemical Equation Wksht.(10pts.)

• Word Equation Worksheet (10pts.)

Infinite Campus Update

• Chemical Reaction Lab(20pts.)

• Balancing Chemical Equation Wksht.(10pts.)

• Word Equation Worksheet (10pts.)

Bell Ringer: Thermochemistry

1. Classify as exothermic (Ex) or endothermic. (Endo) a. C

8

H

18 b. BaBr

2

+ O

2

-------------> CO

2

+ H

2

O + energy

+ energy -----------> Ba + Br

2

2. During an experiment you observed the test tube getting cooler. Explain why this is happening including the terms system and surroundings.

3. Using the activity series determine which reactions will occur in nature:

Mg + FeCl

2

Cu + K(OH)

Al + H

2

(CO

3

)

Thermochemistry Wksht

Work on question 2 on Thermochemistry wksht.

Chemical Reaction Energy Diagram

Chemical Reaction Energy Diagram

• Activation Energy (Ea) : The amount of kinetic energy needed to be absorbed by the reactants in order for the chemical reaction to occur.

H : The amount of kinetic energy released into the surroundings.

Chemical Reaction Energy Diagram

Chemical Reaction Energy Diagram

Activation

Energy

Chemical Reactions Objectives

1.Classify and name compounds in chemical reactions

2.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. (Chpt. 18.1)

Chemical Reaction Rates

Assignment:

Read Section: 18.1 in textbook (pg. 540)

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 37 o C (98 o F) 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.

Time

Conc

Soln. A Concentration vs. Avg. Reaction Times

G1 G2 G3 G4 G5 G6 G7 Avg.

A1

(100%)

15 20 35 16 37 22 25

A2

(75%)

A3

(50%)

A4

(25%)

19

25

50

24

33

39

38

37

34

20

22

29

31

25

38

44

65

78

28

28

34

Activation Energy

Activation energy = minimum energy colliding reactants must have for a reaction to occur. (Energy hump.)

Chemical Reactions Study Guide

Chpt. 9.4 Acids and Bases

Chpt. 11: Balancing, Classifying, and Predicting

Chemical Reactions

Chpt. 18.1: Reaction Rates

Infinite Campus Update

• Classifying Chemical Reaction lab (20pts.)

• Activity Series Lab (10pts.)

• Starch Iodine Lab (10pts.)-due Wed.

• ACT Test for Juniors: Tomorrow, March 6 th

• End of quarter: Thursday, March 8th

Chemical Reaction Study Guide

Catalyst and Energy Change

Infinite Campus Updated

• Activity Series Lab (10pts)

• Classifying Chemical Reaction Lab (15pts)

(Do NOT throw away-Formal Lab Report)

• Starch-Iodine Reaction Lab w/graph. (15pts)

• Quarter End: Tomorrow, March 8 th

(All assignments by Friday).

Formal Lab Report

• Due: March 14 th (next Wed.)

• Written (legible) or Typed (save to flashdrive)

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