Question 1

What mass of oxygen is required to react with calcium to produce 44.8 g calcium oxide?

Accepted Answer

A) 12.8 g 
B) 25.6 g 
C) 6.39 g 
D) 0.399 g 
E) 51.1 g 
A) 12.8 g 
B) 25.6 g 
C) 6.39 g 
D) 0.399 g 
E) 51.1 g

Question 2

What mass of sodium fluoride (used in water fluoridation and the manufacture of insecticides) is required to form 485 g of sulfur tetrafluoride? 3SCl2(l) + 4NaF(s) → SF4(g) + S2Cl2(l) + 4NaCl(s)

Accepted Answer

A) 1.94 kg 
B) 1.51 kg 
C) 754 g 
D) 205 g 
E) 51.3 g 
A) 1.94 kg 
B) 1.51 kg 
C) 754 g 
D) 205 g 
E) 51.3 g

Question 3

Magnesium metal (0.100 mol) and hydrochloric acid (0.500 mol HCl) are combined and react to completion.What volume of hydrogen gas, measured at STP, is produced? Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g) (R = 0.08206 L • atm/K • mol)

Accepted Answer

A) 2.24 L of H2 
B) 4.48 L of H2 
C) 5.60 L of H2 
D) 11.2 L of H2 
E) 22.4 L of H2 
A) 2.24 L of H2 
B) 4.48 L of H2 
C) 5.60 L of H2 
D) 11.2 L of H2 
E) 22.4 L of H2

Question 4

Phosphine, an extremely poisonous and highly reactive gas, reacts with oxygen gas to form tetraphosphorus decaoxide and water. PH3(g) + O2(g) → P4O10(s) + H2O(g) [unbalanced]
Calculate the mass of P4O10(s) formed when 225 g of PH3 reacts with excess oxygen.

Accepted Answer

A) 1880 g 
B) 940.g 
C) 900.g 
D) 470.g 
E) 56.3 g 
A) 1880 g 
B) 940.g 
C) 900.g 
D) 470.g 
E) 56.3 g

Question 5

Aluminum reacts with bromine to form aluminum bromide (used as an acid catalyst in organic synthesis). Al(s) + Br2(l) → Al2Br6(s) [unbalanced]
How many moles of Al are needed to form 2.43 mol of Al2Br6?

Accepted Answer

A) 7.29 mol 
B) 4.86 mol 
C) 2.43 mol 
D) 1.62 mol 
E) 1.22 mol 
A) 7.29 mol 
B) 4.86 mol 
C) 2.43 mol 
D) 1.62 mol 
E) 1.22 mol

Question 6

Lead(II) sulfide was once used in glazing earthenware.It will also react with hydrogen peroxide to form lead(II) sulfate and water.How many grams of hydrogen peroxide are needed to react completely with 265 g of lead(II) sulfide?

Accepted Answer

A) 151 g 
B) 123 g 
C) 50.3 g 
D) 37.7 g 
E) 9.41 g 
A) 151 g 
B) 123 g 
C) 50.3 g 
D) 37.7 g 
E) 9.41 g

Question 7

How much heat is released if 35.0 g of ethanol (C2H5OH) burns in excess oxygen? C2H5OH(l) + 3O2(g) → 2CO2(g) + 3H2O(l) heat of reaction = −1367 kJ/mol

Accepted Answer

A) 1797 kJ 
B) 1367 kJ 
C) 9.61 × 10−4 kJ 
D) 4.78 × 104 kJ 
E) 1040 kJ 
A) 1797 kJ 
B) 1367 kJ 
C) 9.61 × 10−4 kJ 
D) 4.78 × 104 kJ 
E) 1040 kJ

Question 8

Ammonia reacts with diatomic oxygen to form nitric oxide and water vapor as follows: 4NH3 + 5O2 → 4NO + 6H2O What is the maximum amount of water that may be produced if 40.0 g NH3 and 50.0 g O2 are mixed and allowed to react?

Accepted Answer

A) 1.56mol 
B) 1.88 mol 
C) 3.52 mol 
D) 3.91 mol 
E) 2.35 mol 
A) 1.56mol 
B) 1.88 mol 
C) 3.52 mol 
D) 3.91 mol 
E) 2.35 mol

Question 9

What mass of Cr can be produced by the reaction of 44.1 g of Cr2O3 with 35.0 g of Al according to the following chemical equation? 2Al + Cr2O3 → Al2O3 + 2Cr

Accepted Answer

A) 15.1 g 
B) 30.2 g 
C) 67.4 g 
D) 99.9g 
E) 104 g 
A) 15.1 g 
B) 30.2 g 
C) 67.4 g 
D) 99.9g 
E) 104 g

Question 10

What mass of precipitate forms when 25.0 mL of 0.147 M NiCl2 solution reacts with excess sodium phosphate according to the given balanced chemical equation. 3NiCl2(aq) + 2Na3PO4(aq) → Ni3(PO4)2(s) + 6NaCl(aq)

Accepted Answer

A) 0.149 g 
B) 0.448 g 
C) 1.35 g 
D) 0.368 g 
E) 0.234 g 
A) 0.149 g 
B) 0.448 g 
C) 1.35 g 
D) 0.368 g 
E) 0.234 g

Question 11

The first step in the Ostwald process for producing nitric acid is as follows: 4NH3(g) + 5O2(g) → 4NO(g) + 6H2O(g). If the reaction of 15.0 g of ammonia with 15.0 g of oxygen gas yields 8.70 g of nitric oxide, what is the percent yield of this reaction?

Accepted Answer

A) 29.0% 
B) 32.9% 
C) 49.5% 
D) 61.8% 
E) 77.3% 
A) 29.0% 
B) 32.9% 
C) 49.5% 
D) 61.8% 
E) 77.3%

Question 12

What volume of CO2 gas at 645 torr and 800.K could be produced by the decomposition of 45.0 g of CaCO3? CaCO3(s) → CaO(s) + CO2(g) (R = 0.08206 L • atm/K • mol)

Accepted Answer

A) 0.449 L 
B) 22.4 L 
C) 25.0 L 
D) 34.8 L 
E) 45.7 mL 
A) 0.449 L 
B) 22.4 L 
C) 25.0 L 
D) 34.8 L 
E) 45.7 mL

Question 13

The combustion of pentane produces heat according to the following thermochemical equation.C5H 12(l) + 8O2(g) → 5CO2(g) + 6H2O(l) heat of reaction = −3510 kJ/mol How many grams of CO2 is produced per 2.50 × 103 kJ of heat released?

Accepted Answer

A) 6.27 g 
B) 31.3 g 
C) 61.8 g 
D) 157 g 
E) 220 g 
A) 6.27 g 
B) 31.3 g 
C) 61.8 g 
D) 157 g 
E) 220 g

Question 14

Given the following reaction, how much AgCl (in g) can be formed from 25.0 mL of 0.115 M AgNO3 and 45.0 mL of 0.0533 M MgCl2? 2AgNO3(aq) + MgCl2(aq) → 2AgCl(s) + Mg(NO3)2(aq)

Accepted Answer

A) 0.344 g 
B) 0.688 g 
C) 1.10 g 
D) 0.412 g 
E) 0.276 g 
A) 0.344 g 
B) 0.688 g 
C) 1.10 g 
D) 0.412 g 
E) 0.276 g

Question 15

How much heat is evolved if 0.600 kg of SO2 is burned in excess oxygen? 2SO2(g) + O2(g) → 2SO3(g) heat of reaction = −198 kJ/mol

Accepted Answer

A) 5.46 × 10−2 kJ 
B) 927 kJ 
C) 1.85 × 103 kJ 
D) 59,400 kJ 
E) 3.71 × 103 kJ 
A) 5.46 × 10−2 kJ 
B) 927 kJ 
C) 1.85 × 103 kJ 
D) 59,400 kJ 
E) 3.71 × 103 kJ

Question 16

Calculate the volume of H2(g) at 273 K and 2.00 atm that will be formed when 275 mL of 0.725 M HCl solution reacts with 50.0 g Zn(s) to give hydrogen gas and aqueous zinc chloride. (R = 0.08206 L • atm/K • mol)

Accepted Answer

A) 0.56 L 
B) 1.12 L 
C) 2.23 L 
D) 4.47 L 
E) 3.54 L 
A) 0.56 L 
B) 1.12 L 
C) 2.23 L 
D) 4.47 L 
E) 3.54 L

Question 17

If 119.3 g of PCl5 are formed from the reaction of 61.3 g Cl2 with excess PCl3, what is the percent yield? PCl3(g) + Cl2(g) → PCl5(g)

Accepted Answer

A) 94.6% 
B) 66.3% 
C) 57.3% 
D) 51.3% 
E) 48.6% 
A) 94.6% 
B) 66.3% 
C) 57.3% 
D) 51.3% 
E) 48.6%

Question 18

Zinc dissolves in hydrochloric acid to yield hydrogen gas as follows: Zn(s) + 2HCl(aq) → ZnCl2(aq) + H2(g) What mass of hydrogen gas is produced when a 7.35-g sample of zinc dissolves in 500.mL of 1.200 M HCl?

Accepted Answer

A) 0.605 g 
B) 0.113 g 
C) 0.302 g 
D) 0.453 g 
E) 0.227 g 
A) 0.605 g 
B) 0.113 g 
C) 0.302 g 
D) 0.453 g 
E) 0.227 g

Question 19

What volume of chlorine gas at 25°C and 0.950 atm can be produced by the reaction of 12.0 g of MnO2 in excess HCl(aq)? MnO2(s) + 4HCl(aq) → MnCl2(aq) + 2H2O(l) + Cl2(g) (R = 0.08206 L • atm/K • mol)

Accepted Answer

A) 5.36 × 10−3 L 
B) 0.138 L 
C) 0.282 L 
D) 3.09 L 
E) 3.55 L 
A) 5.36 × 10−3 L 
B) 0.138 L 
C) 0.282 L 
D) 3.09 L 
E) 3.55 L

Question 20

How many grams of lead(II) chloride is produced if 13.87 g lead(II) nitrate combines with excess hydrochloric acid to produce lead(II) chloride and nitric acid?

Accepted Answer

A) 5.82 g 
B) 14.33 g 
C) 0.086 g 
D) 11.64 g 
E) 16.52 g 
A) 5.82 g 
B) 14.33 g 
C) 0.086 g 
D) 11.64 g 
E) 16.52 g

What mass of oxygen is required to react with calcium to produce 44.8 g calcium oxide?

What mass of sodium fluoride (used in water fluoridation and the manufacture of insecticides) is required to form 485 g of sulfur tetrafluoride? 3SCl₂(l) + 4NaF(s) → SF₄(g) + S₂Cl₂(l) + 4NaCl(s)

Magnesium metal (0.100 mol) and hydrochloric acid (0.500 mol HCl) are combined and react to completion.What volume of hydrogen gas, measured at STP, is produced? Mg(s) + 2HCl(aq) → MgCl₂(aq) + H₂(g) (R = 0.08206 L • atm/K • mol)

Phosphine, an extremely poisonous and highly reactive gas, reacts with oxygen gas to form tetraphosphorus decaoxide and water. PH₃(g) + O₂(g) → P₄O₁₀(s) + H₂O(g) [unbalanced] Calculate the mass of P₄O₁₀(s) formed when 225 g of PH₃ reacts with excess oxygen.

Aluminum reacts with bromine to form aluminum bromide (used as an acid catalyst in organic synthesis). Al(s) + Br₂(l) → Al₂Br₆(s) [unbalanced] How many moles of Al are needed to form 2.43 mol of Al₂Br₆?

Lead(II) sulfide was once used in glazing earthenware.It will also react with hydrogen peroxide to form lead(II) sulfate and water.How many grams of hydrogen peroxide are needed to react completely with 265 g of lead(II) sulfide?

How much heat is released if 35.0 g of ethanol (C₂H₅OH) burns in excess oxygen? C₂H₅OH(l) + 3O₂(g) → 2CO₂(g) + 3H₂O(l) heat of reaction = −1367 kJ/mol

Ammonia reacts with diatomic oxygen to form nitric oxide and water vapor as follows: 4NH₃ + 5O₂ → 4NO + 6H₂O What is the maximum amount of water that may be produced if 40.0 g NH₃ and 50.0 g O₂ are mixed and allowed to react?

What mass of Cr can be produced by the reaction of 44.1 g of Cr₂O₃ with 35.0 g of Al according to the following chemical equation? 2Al + Cr₂O₃ → Al₂O₃ + 2Cr

What mass of precipitate forms when 25.0 mL of 0.147 M NiCl₂ solution reacts with excess sodium phosphate according to the given balanced chemical equation. 3NiCl₂(aq) + 2Na₃PO₄(aq) → Ni₃(PO₄)₂(s) + 6NaCl(aq)

The first step in the Ostwald process for producing nitric acid is as follows: 4NH₃(g) + 5O₂(g) → 4NO(g) + 6H₂O(g). If the reaction of 15.0 g of ammonia with 15.0 g of oxygen gas yields 8.70 g of nitric oxide, what is the percent yield of this reaction?

What volume of CO₂ gas at 645 torr and 800.K could be produced by the decomposition of 45.0 g of CaCO₃? CaCO₃(s) → CaO(s) + CO₂(g) (R = 0.08206 L • atm/K • mol)

The combustion of pentane produces heat according to the following thermochemical equation.C₅H ₁₂(l) + 8O₂(g) → 5CO₂(g) + 6H₂O(l) heat of reaction = −3510 kJ/mol How many grams of CO₂ is produced per 2.50 × 10³ kJ of heat released?

Given the following reaction, how much AgCl (in g) can be formed from 25.0 mL of 0.115 M AgNO₃ and 45.0 mL of 0.0533 M MgCl₂? 2AgNO₃(aq) + MgCl₂(aq) → 2AgCl(s) + Mg(NO₃)₂(aq)

How much heat is evolved if 0.600 kg of SO₂ is burned in excess oxygen? 2SO₂(g) + O₂(g) → 2SO₃(g) heat of reaction = −198 kJ/mol

Calculate the volume of H₂(g) at 273 K and 2.00 atm that will be formed when 275 mL of 0.725 M HCl solution reacts with 50.0 g Zn(s) to give hydrogen gas and aqueous zinc chloride. (R = 0.08206 L • atm/K • mol)

If 119.3 g of PCl₅ are formed from the reaction of 61.3 g Cl₂ with excess PCl₃, what is the percent yield? PCl₃(g) + Cl₂(g) → PCl₅(g)

Zinc dissolves in hydrochloric acid to yield hydrogen gas as follows: Zn(s) + 2HCl(aq) → ZnCl₂(aq) + H₂(g) What mass of hydrogen gas is produced when a 7.35-g sample of zinc dissolves in 500.mL of 1.200 M HCl?

What volume of chlorine gas at 25°C and 0.950 atm can be produced by the reaction of 12.0 g of MnO₂ in excess HCl(aq)? MnO₂(s) + 4HCl(aq) → MnCl₂(aq) + 2H₂O(l) + Cl₂(g) (R = 0.08206 L • atm/K • mol)

How many grams of lead(II) chloride is produced if 13.87 g lead(II) nitrate combines with excess hydrochloric acid to produce lead(II) chloride and nitric acid?

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Exam 11: Using Balanced Chemical Equations

What mass of oxygen is required to react with calcium to produce 44.8 g calcium oxide?

What mass of sodium fluoride (used in water fluoridation and the manufacture of insecticides) is required to form 485 g of sulfur tetrafluoride? 3SCl2(l) + 4NaF(s) → SF4(g) + S2Cl2(l) + 4NaCl(s)

Magnesium metal (0.100 mol) and hydrochloric acid (0.500 mol HCl) are combined and react to completion.What volume of hydrogen gas, measured at STP, is produced? Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g) (R = 0.08206 L • atm/K • mol)

Phosphine, an extremely poisonous and highly reactive gas, reacts with oxygen gas to form tetraphosphorus decaoxide and water. PH3(g) + O2(g) → P4O10(s) + H2O(g) [unbalanced] Calculate the mass of P4O10(s) formed when 225 g of PH3 reacts with excess oxygen.

Aluminum reacts with bromine to form aluminum bromide (used as an acid catalyst in organic synthesis). Al(s) + Br2(l) → Al2Br6(s) [unbalanced] How many moles of Al are needed to form 2.43 mol of Al2Br6?

Lead(II) sulfide was once used in glazing earthenware.It will also react with hydrogen peroxide to form lead(II) sulfate and water.How many grams of hydrogen peroxide are needed to react completely with 265 g of lead(II) sulfide?

How much heat is released if 35.0 g of ethanol (C2H5OH) burns in excess oxygen? C2H5OH(l) + 3O2(g) → 2CO2(g) + 3H2O(l) heat of reaction = −1367 kJ/mol

Ammonia reacts with diatomic oxygen to form nitric oxide and water vapor as follows: 4NH3 + 5O2 → 4NO + 6H2O What is the maximum amount of water that may be produced if 40.0 g NH3 and 50.0 g O2 are mixed and allowed to react?

What mass of Cr can be produced by the reaction of 44.1 g of Cr2O3 with 35.0 g of Al according to the following chemical equation? 2Al + Cr2O3 → Al2O3 + 2Cr

What mass of precipitate forms when 25.0 mL of 0.147 M NiCl2 solution reacts with excess sodium phosphate according to the given balanced chemical equation. 3NiCl2(aq) + 2Na3PO4(aq) → Ni3(PO4)2(s) + 6NaCl(aq)

The first step in the Ostwald process for producing nitric acid is as follows: 4NH3(g) + 5O2(g) → 4NO(g) + 6H2O(g). If the reaction of 15.0 g of ammonia with 15.0 g of oxygen gas yields 8.70 g of nitric oxide, what is the percent yield of this reaction?

What volume of CO2 gas at 645 torr and 800.K could be produced by the decomposition of 45.0 g of CaCO3? CaCO3(s) → CaO(s) + CO2(g) (R = 0.08206 L • atm/K • mol)

The combustion of pentane produces heat according to the following thermochemical equation.C5H 12(l) + 8O2(g) → 5CO2(g) + 6H2O(l) heat of reaction = −3510 kJ/mol How many grams of CO2 is produced per 2.50 × 103 kJ of heat released?

Given the following reaction, how much AgCl (in g) can be formed from 25.0 mL of 0.115 M AgNO3 and 45.0 mL of 0.0533 M MgCl2? 2AgNO3(aq) + MgCl2(aq) → 2AgCl(s) + Mg(NO3)2(aq)

How much heat is evolved if 0.600 kg of SO2 is burned in excess oxygen? 2SO2(g) + O2(g) → 2SO3(g) heat of reaction = −198 kJ/mol

Calculate the volume of H2(g) at 273 K and 2.00 atm that will be formed when 275 mL of 0.725 M HCl solution reacts with 50.0 g Zn(s) to give hydrogen gas and aqueous zinc chloride. (R = 0.08206 L • atm/K • mol)

If 119.3 g of PCl5 are formed from the reaction of 61.3 g Cl2 with excess PCl3, what is the percent yield? PCl3(g) + Cl2(g) → PCl5(g)

Zinc dissolves in hydrochloric acid to yield hydrogen gas as follows: Zn(s) + 2HCl(aq) → ZnCl2(aq) + H2(g) What mass of hydrogen gas is produced when a 7.35-g sample of zinc dissolves in 500.mL of 1.200 M HCl?

What volume of chlorine gas at 25°C and 0.950 atm can be produced by the reaction of 12.0 g of MnO2 in excess HCl(aq)? MnO2(s) + 4HCl(aq) → MnCl2(aq) + 2H2O(l) + Cl2(g) (R = 0.08206 L • atm/K • mol)

How many grams of lead(II) chloride is produced if 13.87 g lead(II) nitrate combines with excess hydrochloric acid to produce lead(II) chloride and nitric acid?

Atoms and Elements

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Equilibrium

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What mass of sodium fluoride (used in water fluoridation and the manufacture of insecticides) is required to form 485 g of sulfur tetrafluoride? 3SCl₂(l) + 4NaF(s) → SF₄(g) + S₂Cl₂(l) + 4NaCl(s)

Magnesium metal (0.100 mol) and hydrochloric acid (0.500 mol HCl) are combined and react to completion.What volume of hydrogen gas, measured at STP, is produced? Mg(s) + 2HCl(aq) → MgCl₂(aq) + H₂(g) (R = 0.08206 L • atm/K • mol)

Phosphine, an extremely poisonous and highly reactive gas, reacts with oxygen gas to form tetraphosphorus decaoxide and water. PH₃(g) + O₂(g) → P₄O₁₀(s) + H₂O(g) [unbalanced] Calculate the mass of P₄O₁₀(s) formed when 225 g of PH₃ reacts with excess oxygen.

Aluminum reacts with bromine to form aluminum bromide (used as an acid catalyst in organic synthesis). Al(s) + Br₂(l) → Al₂Br₆(s) [unbalanced] How many moles of Al are needed to form 2.43 mol of Al₂Br₆?

How much heat is released if 35.0 g of ethanol (C₂H₅OH) burns in excess oxygen? C₂H₅OH(l) + 3O₂(g) → 2CO₂(g) + 3H₂O(l) heat of reaction = −1367 kJ/mol

Ammonia reacts with diatomic oxygen to form nitric oxide and water vapor as follows: 4NH₃ + 5O₂ → 4NO + 6H₂O What is the maximum amount of water that may be produced if 40.0 g NH₃ and 50.0 g O₂ are mixed and allowed to react?

What mass of Cr can be produced by the reaction of 44.1 g of Cr₂O₃ with 35.0 g of Al according to the following chemical equation? 2Al + Cr₂O₃ → Al₂O₃ + 2Cr

What mass of precipitate forms when 25.0 mL of 0.147 M NiCl₂ solution reacts with excess sodium phosphate according to the given balanced chemical equation. 3NiCl₂(aq) + 2Na₃PO₄(aq) → Ni₃(PO₄)₂(s) + 6NaCl(aq)

The first step in the Ostwald process for producing nitric acid is as follows: 4NH₃(g) + 5O₂(g) → 4NO(g) + 6H₂O(g). If the reaction of 15.0 g of ammonia with 15.0 g of oxygen gas yields 8.70 g of nitric oxide, what is the percent yield of this reaction?

What volume of CO₂ gas at 645 torr and 800.K could be produced by the decomposition of 45.0 g of CaCO₃? CaCO₃(s) → CaO(s) + CO₂(g) (R = 0.08206 L • atm/K • mol)

The combustion of pentane produces heat according to the following thermochemical equation.C₅H ₁₂(l) + 8O₂(g) → 5CO₂(g) + 6H₂O(l) heat of reaction = −3510 kJ/mol How many grams of CO₂ is produced per 2.50 × 10³ kJ of heat released?

Given the following reaction, how much AgCl (in g) can be formed from 25.0 mL of 0.115 M AgNO₃ and 45.0 mL of 0.0533 M MgCl₂? 2AgNO₃(aq) + MgCl₂(aq) → 2AgCl(s) + Mg(NO₃)₂(aq)

How much heat is evolved if 0.600 kg of SO₂ is burned in excess oxygen? 2SO₂(g) + O₂(g) → 2SO₃(g) heat of reaction = −198 kJ/mol

Calculate the volume of H₂(g) at 273 K and 2.00 atm that will be formed when 275 mL of 0.725 M HCl solution reacts with 50.0 g Zn(s) to give hydrogen gas and aqueous zinc chloride. (R = 0.08206 L • atm/K • mol)

If 119.3 g of PCl₅ are formed from the reaction of 61.3 g Cl₂ with excess PCl₃, what is the percent yield? PCl₃(g) + Cl₂(g) → PCl₅(g)

Zinc dissolves in hydrochloric acid to yield hydrogen gas as follows: Zn(s) + 2HCl(aq) → ZnCl₂(aq) + H₂(g) What mass of hydrogen gas is produced when a 7.35-g sample of zinc dissolves in 500.mL of 1.200 M HCl?

What volume of chlorine gas at 25°C and 0.950 atm can be produced by the reaction of 12.0 g of MnO₂ in excess HCl(aq)? MnO₂(s) + 4HCl(aq) → MnCl₂(aq) + 2H₂O(l) + Cl₂(g) (R = 0.08206 L • atm/K • mol)