Science 10Balancing and

ReactionsBooklet

Name:_____________

Semester 2 20101

Notes: Balancing Chemical Equations:________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

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Balance the following chemical equations if required.

1. _____ H2(g) + _____ O2(g)→ _____ H2O(l)

2. _____ Cu(s) + _____ S(s) → _____ Cu2S(s)

3. _____ KCl(s) → _____ K(s) + _____ Cl2(g)

4. _____ N2(g) + _____ H2(g) → _____ NH3(g)

5. _____ Fe2O3(s) + _____ H2(g) → _____ Fe(s) + _____ H2O(l)

6. _____ NaOH(aq) + _____ CO2(g) → _____ Na2CO3(aq) + _____ H2O(l)

7. _____ FeCl3(aq) + _____ NaOH(aq) → _____ Fe(OH)3(s) + _____ NaCl(aq)

8. _____ Al(OH)3(s) + _____ H2SO4(aq) → _____ Al2(SO4)3(aq) + _____ H2O(l)

9. _____ NaCl(s) + _____ H2SO4(aq) → _____ NaHSO4(aq) + _____HCl(g)

10. _____ Ca(OH)2(s) + _____ HCl(aq) → _____ CaCl2(aq) + _____ H2O(l)

11. _____ NO(g) + _____ O2(g) → _____ NO2(g)

12. _____ CuSO4(aq) + _____ NaOH(aq) → _____ Cu(OH)2(aq) + ___Na2SO4(aq)

13. _____ AgNO3(aq) + _____ Cu(s) → _____ Cu(NO3)2(aq) + ___ Ag(s)

14. _____ Na2O2(s) + _____ H2O(l) → _____ NaOH(aq) + _____ O2(g)

15. _____ Pb(C2H3O2)2(aq) + _____ H2S(g) → _____ PbS(s) + _____ HC2H3O2(aq)

16. _____ H2SO4(aq) + _____ Ca3(PO4)2(s) → _____ H3PO4(aq) + _____ CaSO4(s)

17. _____ Pb(NO3)2(aq) + _____ H2SO4(aq) → _____ PbSO4(s) + _____ HNO3(aq)

18. _____ ZnCl2(aq) + _____ (NH4)2S(aq) → _____ ZnS(s) + _____ NH4Cl(aq)

19. _____ Ca(OH)2(aq) + ____ Mg(HCO3)2(aq) → ____ Mg(OH)2(s) + ____ Ca(HCO3)2(aq)

20. _____ Ba(OH)2(aq) + _____ H2SO3(aq) → _____ H2O(l) + _____ BaSO3(s)

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Notes: Types of Reactions:______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

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Classify each of the following reactions by writing F(formation), D (decomposition), SR (single replacement), DR (double replacement), or HC (hydrocarbon combustion) to the left of the equation. Balance the equations using the simplest whole numbers possible.

____ 1. ___Cu(s) + ___O2(g) → ___CuO(s)

____ 2. ___H2O(l) →___H2(g) + ___O2(g)

____ 3. ___Fe(s) + ___ H2O(g) → ___H2(g) + ___Fe3O4(s)

____ 4. ___AsCl3(aq) + ___H2S(aq) → ___As2S3(s) + ___HCl(aq)

____ 5. ___Fe2O3(s) + ___H2(g) → ___Fe(s) + ___H2O(l)

____ 6. ___CaCO3(s) → ___CaO(s) + ___CO2(g)

____ 7. ___Fe(s) + ___S8(s) → ___FeS(s

____ 8. ___H2S(aq) + ___KOH(aq) → ___HOH(l) + ___K2S(aq)

____ 9. ___NaCl(l) → ___Na(l) + ___Cl2(g)

____ 10. ___Al(s) + ___H2SO4(aq) → ___H2(g) + ___Al2(SO4)3(aq)

____ 11. ___H3PO4(aq) + ___NH4OH(aq) →___HOH(l) + ___(NH4)3PO4(aq)

____ 12. ___C3H8(g) + ___O2(g) → ___CO2(g) + ___H2O(g)

____ 13. ___Al(s) + ___O2(g) → ___Al2O3(s)

____ 14. ___CH4(g) + ___O2(g)→ __CO2(g) + ___H2O(g)

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The 5 Types of ReactionsFormation Reactions:

element + element → compounde.g. 2 Mg(s) + O2(g) → 2 MnO(s)

Decomposition Reactions:compound → element + elemtent

e.g. 8 HgS(s) → 8 Hg(l) + S8(s)

Notes: 1. Formation and decomposition reactions generally involve only pure substances.

2. Remember when predicting products to write the correct chemical formulas first and then balance the equation.

____ 1. The first step in the production of sulfuric acid is to burn sulfur___S8(s) + ___O2(g) → ___SO2(g)

____ 2. In 1774 Joseph Priestly discovered oxygen by decomposing the calx of mercury.___HgO(s) → ___Hg(l) + ___O2(g)

____ 3. Molten table salt is industrially decomposed to produce molten sodium.___NaCl(l) → ___Na(l) + ___Cl2(g)

____ 4. Nitrogen from the air reacts with hydrogen to produce ammonia for fertilizers.___N2(g) + ___H2(g) → ___NH3(g)

____ 5. Rocket fuel burns to propel a satellite into space.___H2(g) + ___O2(g) → ___H2O(g)

____ 6. Copper (II) oxide decomposes to form solid copper and oxygen.___CuO(s) →

____ 7. Barbeque charcoal undergoes incomplete combustion to produce carbon monoxide.

___C(s) + ___O2(g) →

____ 8. Freshly cut lithium reacts with nitrogen from the air.___Li(s) + ___N2(g) →

____ 9. A silver spoon or coin tarnishes when exposed to sulfur.___Ag(s) + ___S8(s) →

____ 10. Molten lye is decomposed industrially into its elements.___NaOH(l) →

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Single and Double Replacement Reactions

1. Classify each of the following reactions by writing F, D, SR, DR, or HC to the left of the equation. Balance the equations using the simplest whole numbers possible.

2. Complex ions are assumed to remain intact and are balanced as complete units.3. It is convenient for balancing to write water as HOH for single and double replacement

reaction.4. Remember to read the balanced equations in terms of moles.

Single replacement ReactionsElement + compound element + compound Cl2(aq) + 2 NaI(aq) I2(aq) + NaCl(aq)

Double Replacement ReactionsCompound + compound compound + compound

Pb(NO3)2(aq) + 2 KI(aq) PbI2(s) + 2 KNO3(aq)

Note: Use the solubility table on page of your text to predict the solubility of the products of single and double replacement reactions in water.

____ 1. Sodium metal reacts vigorously with water.___Na(s) + ___HOH(l) → ___H2(g) + ___NaOH(aq)

____ 2. Hydrogen chloride gas is produced in the laboratory from table salt.___NaCl(s) + ___H2SO4(aq) → ___HCl(g) + ___Na2SO4(aq)

____ 3. Molten iron is produced in the highly exothermic thermite reaction.___Al(s) + ___Fe2O3(s) → ___Fe(l) + ___Al2O3(s)

____ 4. Slaked lime precipitates magnesium ion from hard water.___Ca(OH)2(aq) + ___Mg(HCO3)2(aq) → ___Mg(OH)2(s) + ___Ca(HCO3)2(aq)

____ 5. Aluminum was first produced in 1825 by Hans Oersted using the following reaction.

___K(s) + ___AlCl3(s) → ___Al(s) + ___KCl(s)

____ 6. Silver is recovered from silver ore by converting the ore into silver sulfate which is then reacted with copper(II).

___Cu(s) + ___Ag2SO4(aq) →____ 7. Phosphoric acid is produced at a fertilizer plant.

___H2SO4(aq) + ___Ca3(PO4)2(s) →____ 8. Bromine is commercially produced from MgBr2

___Cl2(g) + ___MgBr2(aq) →____ 9. Hydrogen sulfide (sour) gas from a wild natural gas well reacts with the lead(II) chromate pigment in paint on homes.

___H2S(g) + ___PbCrO4(s) →____ 10. Hydrogen sulfide gas from a wild sour natural gas well reacts with the silver in

cutlery and ornaments at home.___H2S(g) + ___Ag(s) →

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1. Follow previous instructions concerning identification of reaction type, writing correct formulas, indicating the state of matter and balancing the chemical reaction.

2. Except for methane the formula and phase for the hydrocarbons will be provided in all questions.

3. For other types of reactions the total equation will be given. Products can not always be predicted easily.

4. Remember to react the balanced equations in terms of moles.

Hydrocarbon Combustion ReactionsA hydrocarbon + oxygen → carbon dioxide + water vapour 2 C2H6(g) + 7 O2(g) → 4 CO2(g) + 6 H2O(g)

Notes:1. Write water as H2O(g) in equations for hydrocarbon combustion reactions. Written as

H2O, balancing is easier. Because of the heat produced in hydrocarbon combustion reactions water is produced as a gas (H2O(g)).

2. Balance C and H atoms first, O atoms last.

____ 1. A bunsen burner, gas furnace and gas hot-water tank all burn natural gas.___CH4(g) + ___O2(g) → ___CO2(g) + ___H2O(g)

____ 2. Propane is used as a fuel for trailers and where natural gas is not available.

___C3H8(g) + ___O2(g) →

____ 3. Gasoline is mixed with air in the carburetor and then exploding by a spark in the cylinder of a car motor.

___C8H18(l) + ___O2(g) →

____ 4. Kerosene (assume C14H30) is a mixture of hydrocarbons used as a fuel for stoves and lanterns and for diesel and jet engines.

___C14H30(l) + ___O2(g) → ___CO2(g) + ___H2O(g)

____ 5. Oxyacetylene torches are used to produce high temperatures for cutting and welding metals such as steel. This involves burning acetylene.

___C2H2(g) + ___O2(g) →

____ 6. Butane is burned by lighters.___C4H10 + ___O2(g) →

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Writing and Balancing Equations Review

1. For each of the following equations, identify the type of reaction and add coefficients to balance the equation

Typea. ____ ___N2(g) + ___H2(g) → ___NH3(g)

b. ____ ___Na(s) + ___Cl2(g) → ___NaCl(s)

c. ____ ___H2O(l) → ___H2(g) + ___O2(g)

d. ____ ___Na(s) + ___H2O(l) →___NaOH(aq) + ___H2(g)

e. ____ ___Zn(s) + ___HCl(aq) →___ZnCl2(aq) + ___H2(g)

f. ____ ___CH4(g) + ___O2(g) →___CO2(g) + ___H2O(g)

g. ____ ___P4(s) + ___Cl2(g) → ___PCl5(s)

h. ____ ___CoCl2(aq) + ___Zn(s) → ___ZnCl(aq) + ___Co(s)

i. ____ ___Na3PO4(aq) + ___MgCl2(aq) →__Mg3(PO4)2(s) + ___NaCl(aq)

j. ____ ___C4H10(g) + ___O2(g) → ___CO2(g) + ___H2O(g)

k. ____ ___P2O5(s) → ___P4(s) + ___O2(g)

l. ____ ___Al(s) + ___Cu(NO2)2(aq)→___Cu(s) + ___Al(NO2)3(aq)

m. ____ ___CaC2(s) + ___H2O(l) → ___C2H2(g) + ___Ca(OH)2(s)

2. For each of the following word equations or descriptions, write and balance an equation to represent the reaction. Identify the type of reaction.

a. Magnesium reacts with hydrochloric acid to form magnesium chloride and hydrogen gas, H2.

b. Aluminum metal reacts with iron(III) oxide to form iron metal and aluminum oxide.

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c. Calcium hydroxide reacts with sulfuric acid to produce calcium sulfate and water.

d. Elemental sulfur, S8, reacts with oxygen gas, O2, to form sulfur trioxide gas.

e. Lead(II) oxide is decomposed into lead metal and oxygen gas, O2.

f. Propane gas, C3H8, burns by combining with oxygen gas to produce carbon dioxide gas and water vapour.

3. Writing and Balancing Equations

In doing these problems, refer to the classifications of reactions. Write balanced equations for the following.

a. ___ H2(g) + ___O2(g) →

b. ___KCl(s) →

c. ___Cl2(g) + ___NaI →

d. ___KCl(aq) + ___AgNO3(aq) →

e. ___Pb(s) + ___ZnBr2(aq) →

f. ___BaCl2(aq) + ___Na2SO4(aq) →

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Reaction Prediction Test Name: ___________________

In each of the following: (4 marks each)a. State the type of reaction expected (1 mark)b. Write the balanced equation for the reaction (1 mark – symbols)

(1 mark – states of matter) (1 mark – balancing)

1. aluminum plus hydrochloric acid

2. propane(C3H8) burns

3. calcium hydroxide plus nitric acid

4. magnesium plus zinc nitrate

5. iron(III) oxide →

6. zinc chloride plus hydrogen sulfide

7. methane plus oxygen

8. NaCl(s) →

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9. C4H10(g) + O2(g) →

10. Al(s) + F2(g) →

11. NH3(g) + O2(g) H2O(g) + NO2(g)

12. water decomposes into its elements

13. sulfur dioxide is formed from its elements

14. calcium phosphate reacts with sodium carbonate

15. hydrochloric acid neutralizes potassium hydroxide

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Worksheet # 7 Moles

1. Calculate the molar mass of the following compounds:

Formula Name Molar Mass (g/mol)

Na2SO4(s)

Ca(NO3)2(s)

N2O5(s)

K2Cr2O7(s)

Al2O3(s)

(NH4)2SO4(s)

3. Fill in the blanks of the following table:

Compound Number of Atoms or Molecules

Number of Moles Mass(g)

NaCl(s) 6.02 x 1025

AgNO3(s) 0.650

K(s) 1.50 x 1023

Zn(s) 200 g

Cl2(g) 3.20

NaOH(s) 60.0 g

HCl(g) 1.20 x 1025

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Worksheet # 8Find the number of Moles or Mass of the following samples.

Compound Name Molar Mass Number of Moles Mass(g)CH4(g) 34.7

CuCl2(s) 115

Ca(NO3)2(s) 455

CO2(g) 6.75

ZnS(s) 885

(NH4)2SO4(s) 75

C2H6(g) ethane 2.55

MgBr2(s) 25.5

NiCl2(s) 33.4

Fe2O3(s) 0.115

HCl(g) 5.75

K2Cr2O7(s) 0.0125

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Worksheet 8: Part 2 Mole Calculations

Complete the following table. Show all work as in the example.

Name and Formula Molar Mass (M) # Moles(n) Mass(m)

Example:carbon tetrachlorideCCl4(l)

Toxic solvent

1 C = 1 x 12.01 = 12.014 Cl = 3 x 35.45 = 141.80 153.81 g/mol

1.2 mol

m = nMCCl4 = 1.2 mol x 153.81 g/mol = 1.8 x 102 g or 0.18 kg

sodium chloride

(table salt)

0.25 mol

KOH(s)

(caustic soda)

4.61 g

(NH4)2SO4(s)

(fertilizer)

0.400 mol

sodium carbonate

(washing soda)

0.22 mol

Ca(NO3)2(s)

8.20 g

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Name and Formula Molar Mass (M) # Moles(n) Mass(m)

sodium dichromate

13.1 g

sulfur dioxide

1.60 mol

K2CO3(s)

82.8 g

aluminum oxide

25.5 g

Cu(ClO3)2(s)

2.50 mol

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