Academic ChemistryChapter 8

Chemical Equations and Reactions

Essential Question:

What are some of the chemical reactions that occur within our environment every day?

Vocabulary:

Chemical Equation (241) Activity Series (265) Synthesis Reaction(256)Decomposition Reaction (259)Single Replacement Reaction (261) Precipitate (242)Reversible Reaction (246) Double Replacement Reaction (262) Composition Reaction(256)Formula Equation (244) Displacement Reaction (261) Coefficient (243)Word Equation (246) Electrolysis (259) Combustion Reaction (263)

Textbook Readings and Homework:

8 – 1 Describing Chemical Reactions p241-254 p 254 Problems # 1,3,58 – 2 Types of Chemical Reactions p256-264 p 264 Problems # 1,2,3,4acdf8 – 3 Activity Series of the Elements p265-267 p 267 Problems # 1-4EOC Page 269 #1, 16a, 18, 21, 24, 28, 29, 30acd, 47ac

Objectives:

1. Recognize the signs of a chemical reaction by observation.2. Interpret the meaning of symbols used in writing chemical equations.3. Describe chemical reactions by writing balanced chemical equations.4. Explain how the Law of Conservation of Mass is related to a balanced chemical equation.5. Classify reactions as belonging to one of five general types of chemical reactions.6. Predict the products of a balanced chemical reaction using the general forms as a guide.7. Predict the products of and balance single replacement reactions using the activity series.8. Differentiate between endothermic and exothermic reactions.

Activities and Labs:

Various Demos of Reaction TypesLab: Chemical ReactionsLab: Activity SeriesLab: Balancing Chemical Reactions with Ion Cards

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Match the symbol on the left with its appropriate description on the right. (a) A precipitate forms.

(b) A gas forms. (c) A reversible reaction occurs.

(l ) (d) Heat is applied to the reactants. (aq) (e) A chemical is dissolved in water.

(f ) A chemical is in the liquid state.

Answer the following:2. A (physical or chemical) change is a change of matter from one form to another without a

change in chemical properties. 3. A (physical or chemical) change is a change that occurs when a substance changes composition

by forming one or more new substances. 

Mark the following as true or false4. Color change is evidence that a chemical change may have occurred. 5. Fizzing or foaming is evidence that a chemical change may have occurred.6. Production of sound is evidence that a chemical change may have occurred.7. Production of heat or light is evidence that a chemical change may have occurred.8. Production of an odor is evidence that a chemical change may have occurred.9. Chemical changes can not be reversed by physical changes.

Directions: Fill in each blank on the right side of the sheet with the correct term from the word list; Arrow, exothermic, chemical equation, reaction, precipitate, coefficient, product, catalyst, reactant, delta (),endothermic

Another name for a chemical change is a(n) Such a change can be represented

by means of a written statement called a(n) . The symbol for the word “yields” in such

a statement is a(n) . Any substance written to the left of this symbol is called a(n)

Any substance written to the right of this symbol is called a(n) . A

number written just to the left of a chemical formula is called a(n) .

A chemical change in which energy is absorbed is called a(n) reaction. One in

which energy is released is called a(n) reaction. If the change is caused by heat supplied

to the reaction, the Greek symbol is often written above the “yields” symbol in the

equation. Any charged particle that is present in the solution, but that does not react during a reaction, is

usually omitted from the net equation; it is called a(n) . A solid substance produced by

such a reaction is called a(n) .

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BALANCING CHEMICAL EQUATIONS

Rewrite and balance the equations below.

1. N2 + H2 NH3

2. KClO3 KCl + O2

3. NaCl + F 2 NaF + Cl2

4. H2 + O2 H2O

5. AgNO3 + MgCl2 AgCl + Mg(NO3)2

6. AlBr 3 + K2SO4 KBr + Al2(SO4)3

7. CH4 + O2 CO2 + H2O

8. C3H8 + O2 CO2 + H2O

9. C8H18 + O2 CO2 + H2O

10. FeCl3 + NaOH Fe(OH)3 + NaCl

11. P + O2 P2O5

12. Na + H2O NaOH + H2

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13. Ag2O Ag + O2

14. S8 + O2 SO3

15. CO2 + H2O C6H12O6 + O2

16. K + MgBr2 KBr + Mg

17. HCl + CaCO3 CaCl2 + H2O + CO2

18. Zn + HCl ZnCl2 + H2          

19. FeCl3 + Na2CO3 Fe2(CO3)3 + NaCl      

20. Na + H2O NaOH + H2         

21. C2H6 + O2 CO2 + H2O            

22. HgO Hg + O2       

23. CaCl2 + Na3PO4 NaCl + Ca3(PO4)2          

24. N2O5 + H2O  HNO3           

25. Mg + CuCl2 MgCl2 + Cu         

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CLASSIFICATION OF CHEMICAL REACTIONS

Classify the reactions below as synthesis, decomposition, single replacement (cationic or anionic) or double replacement.

1. H2 + O2 H2O

2. H2O H2 + O2

3. Zn + H2SO4 ZnSO4 + H2

4. CO + O2 CO2

5. HgO Hg + O2

6. KBr + Cl2 KCl + Br2

7. CaO + H2O Ca(OH)2

8. AgNO3 + NaCl AgCl + NaNO3

9. H2O2 H2O + O2

10. Ca(OH)2 + H2SO4 CaSO4 + H2O

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WORD EQUATIONS

Write the word equation below as chemical equations and balance.

1. zinc + lead (II) nitrate yield zinc(II) nitrate + lead

2. aluminum bromide + chlorine yield aluminum chloride + bromine

3. sodium phosphate + calcium chloride yield calcium phosphate + sodium chloride

4. potassium chlorate when heated yields potassium chloride + oxygen gas

5. aluminum + hydrochloric acid yield aluminum chloride + hydrogen gas

6. calcium hydroxide + phosphoric acid yield calcium phosphate + water

7. copper + sulfuric acid yield copper (II) sulfate + water + sulfur dioxide

8. hydrogen + nitrogen monoxide yield water + nitrogen

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9. potassium chloride + silver(II) nitrate → potassium nitrate + silver(II) chloride

10. aluminum hydroxide + sodium nitrate → aluminum nitrate + sodium hydroxide

11. iron metal + copper (II) sulfate→ iron (III) sulfate + copper metal

12. aluminum metal + copper (II) chloride → aluminum chloride + copper metal

13. sodium chlorate → sodium chloride + oxygen gas

14. calcium carbonate → calcium oxide + carbon dioxide gas

15. zinc metal + oxygen gas → zinc(II) oxide

16. chlorine gas + sodium metal → sodium chloride

17. aluminum sulfate + barium chloride → aluminum chloride + barium sulfate

18. sodium hydrogen carbonate → sodium carbonate + carbon dioxide + water

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MORE WORD EQUATIONS – Write the Formula and Balance

1) Calcium reacts with copper (II) nitrate to form calcium nitrate and copper metal

2) Zinc and lead (II) nitrate react to form zinc(I) nitrate and lead.

3) Aluminum bromide and chlorine gas react to form aluminum chloride and bromine gas.

4) Sodium phosphate and calcium chloride react to form calcium phosphate and sodium chloride.

5) Potassium metal and chlorine gas combine to form potassium chloride.

6) Hydrogen gas and nitrogen monoxide react to form water and nitrogen gas.

7) The reaction of copper (II) oxide with hydrogen to form copper metal and water.

8) The reaction of iron metal with oxygen to form iron (III) oxide.

9) Potassium reacts with bromine to form potassium bromide.

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10) Sodium metal reacts violently with water to produce sodium hydroxide and hydrogen.COMPLETING, IDENTIFYING, AND BALANCING EQUATIONS

Complete each equation, identify the type of reaction and balance the following equations.

Type of Reaction Predict Products & Balance

1. _______________ Al + O2

2. _______________ NaBrO3 O2 +

3. _______________ FeCl3

4. _______________ Al(OH)3 + NaNO3

5. _______________ CaCO3 (calcium oxide) + (carbon dioxide)

6. _______________ K + H3PO2

7. _______________ Al + CuSO4

8. _______________ NaCl + S

9. _______________ K2S + Ba(OH)2

10. _______________ BeF2 + Mg

11. _______________ Na + S

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12. _______________ FeS + HCI

Complete the word equation for the following chemical equations. Then, write the balanced equation. Indicate the type of reaction on the line to the left of the equation. Classify each reaction as: (SD) -single displacement, (DD)- double displacement, (D) -decomposition or (S) -synthesis

1. aluminum sulfate + calcium phosphate

2. magnesium chloride + silver(II) nitrate

3. sodium chlorate

4. hydrogen gas + oxygen gas

5. Zinc(I) metal + copper (II) nitrate

6. sulfurous acid (H2SO3)

7. copper (II) oxide + sulfuric acid (H2SO3)

8. nitrogen gas + hydrogen gas

9. sodium iodide + chlorine gas

10. copper (II) hydroxide

11. ammonia gas + hydrochloric acid

12. potassium metal + water

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CHEMICAL REACTIONS

Predict the products of the reactions below. Then, write the balanced equation and classify the reaction.

1. magnesium bromide + chlorine

2. aluminum + iron (III) oxide

3. silver(II) nitrate + zinc(II) chloride

4. hydrogen peroxide (catalyzed by manganese dioxide)

5. zinc (II) + hydrochloric acid

6. sulfuric acid + sodium hydroxide

7. sodium + hydrogen

8. acetic acid + copper(II)

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Activity Series

1. How is the activity series useful in predicting chemical behavior?

2. Based on the activity series, predict whether each of the following possible reactions listed will occur. For the reactions that do not occur, write NR (no reaction). For the reactions that will occur, predict the products and balance the equation.

50C

Zn(II) (s) + H2O (l)

Sn(IV) (s) + O2 (g)

Cd (II)(s) + Pb(NO3)2 (aq)

Cu (II)(s) + HCl (aq)

Cr (II)(s) + H2O (l)

Pt (II)(s) + O2 (g)

Mg (s) + steam

Ni (II) (s) + H2O (l)

Br2 (l) + KI (aq)

Au(II) (s) + HCl (aq)

Cd (II)(s) + HCl (aq)

Mg (s) + Co(NO3)2 (aq)

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Activity Series

An activity series is a series of elements that have similar properties that are arranged in

descending order of chemical activity. Using the following experimental data collected

from a series of single replacement reactions, arrange the metals in order of decreasing

activity (most active to least) Show your reasoning.

Cu(NO3)2 + Zn → Reaction

Cu(NO3)2 + Mg→ Reaction

Zn(NO3)2 + Mg → Reaction

Zn(NO3)2 + Cu → No reaction

Mg(NO3)2 + Zn → No reaction

Mg(NO3)2 + Cu → No reaction

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Double Displacement Problems

Predict the products and balance all the equations.

1. ____ K2CO3 (aq) + ____ ZnCl2 (aq)

2. ____FeCl3 (aq)+ ____ K2SO4 (aq)

3. ____ AlBr3 (aq) + ____ K2SO4 (aq)

4. ____ FeCl3 (aq) + ____ NaOH (aq)

55 ____ NaBr (aq) + ____ CaF2 (aq)

6. ____ AgNO3(aq) + ____ NaCl (aq)

7. ____ K3PO4(aq) + ____Ba(NO3)2(aq)

8. ____ AgNO3(aq) +____ KBr(aq)

9. ____ KOH(aq) + ____ZnCl2(aq)

555 ____CoCl2(aq) + ____ Na3PO4(aq)

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