Question 1

How many moles of pyridine (C5H5N)are contained in 4.14 g of pyridine?

Accepted Answer

A) 0.0523 
B) 327 
C) 6.88 × 10-24 
D) 2.49 ×1024 
E) 79.1 
A) 0.0523 
B) 327 
C) 6.88 × 10-24 
D) 2.49 ×1024 
E) 79.1

Question 2

Propane (C3H8)reacts with oxygen in the air to produce carbon dioxide and water. In a particular experiment, 38.0 grams of carbon dioxide are produced from the reaction of 22.05 grams of propane with excess oxygen. What is the % yield in this reaction?

Accepted Answer

A) 38.0 
B) 57.6 
C) 66.0 
D) 86.4 
E) 94.5 
A) 38.0 
B) 57.6 
C) 66.0 
D) 86.4 
E) 94.5

Question 3

A great deal of the carbon dioxide produced by the combustion of fossil fuels is absorbed into the oceans.

Accepted Answer

A) True 
 B)False

Question 4

Which of the following are combustion reactions? 1) CH4 (g) + O2 (g) → CO2 (g) + H2O (l)
2) CaO (s) + CO2 (g) → CaCO3 (s)
3) PbCO3 (s) → PbO (s) + CO2 (g)
4) CH3OH (l) + O2 (g) → CO2 (g) + H2O (l)

Accepted Answer

A) 1 and 4 
B) 1, 2, 3, and 4 
C) 1, 3, and 4 
D) 2, 3, and 4 
E) 3 and 4 
A) 1 and 4 
B) 1, 2, 3, and 4 
C) 1, 3, and 4 
D) 2, 3, and 4 
E) 3 and 4

Question 5

What is the coefficient of O2 when the following equation is completed and balanced? C4H8O2 + O2 → ________

Accepted Answer

A) 2 
B) 3 
C) 5 
D) 6 
E) 1 
A) 2 
B) 3 
C) 5 
D) 6 
E) 1

Question 6

How many grams of oxygen are in 56 g of C2H2O2?

Accepted Answer

A) 11 
B) 19 
C) 26 
D) 31 
E) 49 
A) 11 
B) 19 
C) 26 
D) 31 
E) 49

Question 7

The combustion of ammonia in the presence of excess oxygen yields NO2 and H2O: 4 NH3 (g) + 7O2 (g) → 4 NO2 (g) + 6 H2O (g)
The combustion of 14.4 g of ammonia consumes ________ g of oxygen.

Accepted Answer

A) 13.5 
B) 28.8 
C) 54.1 
D) 47.3 
E) 94.6 
A) 13.5 
B) 28.8 
C) 54.1 
D) 47.3 
E) 94.6

Question 8

The formula of nitrobenzene is C6H5NO2. The molecular weight of this compound is ________ amu.

Accepted Answer

A) 107.11 
B) 43.03 
C) 109.10 
D) 123.11 
E) 3.06 
A) 107.11 
B) 43.03 
C) 109.10 
D) 123.11 
E) 3.06

Question 9

What is the empirical formula of a compound that contains 27.0% S, 13.4% O, and 59.6% Cl by mass?

Accepted Answer

A) SOCl 
B) SOCl2 
C) S2OCl 
D) SO2Cl 
E) ClSO4 
A) SOCl 
B) SOCl2 
C) S2OCl 
D) SO2Cl 
E) ClSO4

Question 10

The molecular weight is always a whole-number multiple of the empirical formula weight.

Accepted Answer

A) True 
 B)False

Question 11

What is the empirical formula of a compound that is 66.6% C, 11.2% H, and 22.2% O by mass?

Accepted Answer

A) C4HO 
B) C6HO2 
C) C8H16O2 
D) C6H11O 
E) C4H8O 
A) C4HO 
B) C6HO2 
C) C8H16O2 
D) C6H11O 
E) C4H8O

Question 12

What is the mass % of carbon in dimethylsulfoxide (C2H6SO)rounded to three significant figures?

Accepted Answer

A) 25.4 
B) 28.6 
C) 30.7 
D) 7.74 
E) 78.1 
A) 25.4 
B) 28.6 
C) 30.7 
D) 7.74 
E) 78.1

Question 13

Lead (II)carbonate decomposes to give lead (II)oxide and carbon dioxide: PbCO3 (s) → PbO (s) + CO2 (g)
If the reaction yield is 95.7%, how many grams of lead (II)oxide will be produced by the decomposition of 2.50 g of lead (II)carbonate?

Accepted Answer

A) 1.04 
B) 1.55 
C) 2.18 
D) 4.00 
E) 5.55 
A) 1.04 
B) 1.55 
C) 2.18 
D) 4.00 
E) 5.55

Question 14

The formula weight of magnesium fluoride (MgF2), rounded to one decimal place, is ________ amu.

Accepted Answer

A) 86.6 
B) 43.3 
C) 62.3 
D) 67.6 
E) 92.9 
A) 86.6 
B) 43.3 
C) 62.3 
D) 67.6 
E) 92.9

Question 15

The formula weight of silver chromate (Ag2CrO4)is ________ amu.

Accepted Answer

A) 159.87 
B) 223.87 
C) 331.73 
D) 339.86 
E) 175.87 
A) 159.87 
B) 223.87 
C) 331.73 
D) 339.86 
E) 175.87

Question 16

A compound that is composed of only carbon and hydrogen contains 85.7% C and 14.3% H by mass. What is the empirical formula of the compound?

Accepted Answer

A) CH2 
B) C2H4 
C) CH4 
D) C4H8 
E) C86H14 
A) CH2 
B) C2H4 
C) CH4 
D) C4H8 
E) C86H14

Question 17

Silver nitrate and aluminum chloride react with each other by exchanging anions: 3AgNO3 (aq) + AlCl3 (aq) → Al(NO3)3 (aq) + 3AgCl (s)
What mass in grams of AgCl is produced when 4.22 g of AgNO3 react with 7.73 g of AlCl3?

Accepted Answer

A) 17.6 
B) 4.22 
C) 24.9 
D) 3.56 
E) 11.9 
A) 17.6 
B) 4.22 
C) 24.9 
D) 3.56 
E) 11.9

Question 18

Under appropriate conditions, nitrogen and hydrogen undergo a combination reaction to yield ammonia:
N2 (g) + 3H2 (g) → 2NH3 (g)
A 9.3-g sample of hydrogen requires ________ g of N2 for a complete reaction.

Accepted Answer

Exam 3: Stoichiometry: Calculations With Chemical Formulas and Equations

How many moles of pyridine (C5H5N)are contained in 4.14 g of pyridine?

Propane (C3H8)reacts with oxygen in the air to produce carbon dioxide and water. In a particular experiment, 38.0 grams of carbon dioxide are produced from the reaction of 22.05 grams of propane with excess oxygen. What is the % yield in this reaction?

A great deal of the carbon dioxide produced by the combustion of fossil fuels is absorbed into the oceans.

Which of the following are combustion reactions? 1) CH4 (g) + O2 (g) → CO2 (g) + H2O (l) 2) CaO (s) + CO2 (g) → CaCO3 (s) 3) PbCO3 (s) → PbO (s) + CO2 (g) 4) CH3OH (l) + O2 (g) → CO2 (g) + H2O (l)

What is the coefficient of O2 when the following equation is completed and balanced? C4H8O2 + O2 → ________

How many grams of oxygen are in 56 g of C2H2O2?

The combustion of ammonia in the presence of excess oxygen yields NO2 and H2O: 4 NH3 (g) + 7O2 (g) → 4 NO2 (g) + 6 H2O (g) The combustion of 14.4 g of ammonia consumes ________ g of oxygen.

The formula of nitrobenzene is C6H5NO2. The molecular weight of this compound is ________ amu.

What is the empirical formula of a compound that contains 27.0% S, 13.4% O, and 59.6% Cl by mass?

The molecular weight is always a whole-number multiple of the empirical formula weight.

What is the empirical formula of a compound that is 66.6% C, 11.2% H, and 22.2% O by mass?

What is the mass % of carbon in dimethylsulfoxide (C2H6SO)rounded to three significant figures?

Lead (II)carbonate decomposes to give lead (II)oxide and carbon dioxide: PbCO3 (s) → PbO (s) + CO2 (g) If the reaction yield is 95.7%, how many grams of lead (II)oxide will be produced by the decomposition of 2.50 g of lead (II)carbonate?

The formula weight of magnesium fluoride (MgF2), rounded to one decimal place, is ________ amu.

The formula weight of silver chromate (Ag2CrO4)is ________ amu.

A compound that is composed of only carbon and hydrogen contains 85.7% C and 14.3% H by mass. What is the empirical formula of the compound?

Silver nitrate and aluminum chloride react with each other by exchanging anions: 3AgNO3 (aq) + AlCl3 (aq) → Al(NO3)3 (aq) + 3AgCl (s) What mass in grams of AgCl is produced when 4.22 g of AgNO3 react with 7.73 g of AlCl3?

Under appropriate conditions, nitrogen and hydrogen undergo a combination reaction to yield ammonia: N2 (g) + 3H2 (g) → 2NH3 (g) A 9.3-g sample of hydrogen requires ________ g of N2 for a complete reaction.

Introduction: Matter and Measurement

Atoms, Molecules, and Ions

Aqueous Reactions and Solution Stoichiometry

Thermochemistry

Electronic Structure of Atoms

Periodic Properties of the Elements

Basic Concepts of Chemical Bonding

Molecular Geometry and Bonding Theories

Gases

Liquids and Intermolecular Forces

Solids and Modern Materials

Properties of Solutions

Chemical Kinetics

Chemical Equilibrium

Acid-Base Equilibria

Additional Aspects of Aqueous Equilibria

Chemistry of the Environment

Chemical Thermodynamics

Electrochemistry

Nuclear Chemistry

Chemistry of the Nonmetals

Transition Metals and Coordination Chemistry

The Chemistry of Life: Organic and Biological Chemistry

Filters

How many moles of pyridine (C₅H₅N)are contained in 4.14 g of pyridine?

Propane (C₃H₈)reacts with oxygen in the air to produce carbon dioxide and water. In a particular experiment, 38.0 grams of carbon dioxide are produced from the reaction of 22.05 grams of propane with excess oxygen. What is the % yield in this reaction?

Which of the following are combustion reactions? 1) CH₄ (g) + O₂ (g) → CO₂ (g) + H₂O (l) 2) CaO (s) + CO₂ (g) → CaCO₃ (s) 3) PbCO₃ (s) → PbO (s) + CO₂ (g) 4) CH₃OH (l) + O₂ (g) → CO₂ (g) + H₂O (l)

What is the coefficient of O₂ when the following equation is completed and balanced? C₄H₈O₂ + O₂ → ________

How many grams of oxygen are in 56 g of C₂H₂O₂?

The combustion of ammonia in the presence of excess oxygen yields NO₂ and H₂O: 4 NH₃ (g) + 7O₂ (g) → 4 NO₂ (g) + 6 H₂O (g) The combustion of 14.4 g of ammonia consumes ________ g of oxygen.

The formula of nitrobenzene is C₆H₅NO₂. The molecular weight of this compound is ________ amu.

What is the mass % of carbon in dimethylsulfoxide (C₂H₆SO)rounded to three significant figures?

Lead (II)carbonate decomposes to give lead (II)oxide and carbon dioxide: PbCO₃ (s) → PbO (s) + CO₂ (g) If the reaction yield is 95.7%, how many grams of lead (II)oxide will be produced by the decomposition of 2.50 g of lead (II)carbonate?

The formula weight of magnesium fluoride (MgF₂), rounded to one decimal place, is ________ amu.

The formula weight of silver chromate (Ag₂CrO₄)is ________ amu.

Silver nitrate and aluminum chloride react with each other by exchanging anions: 3AgNO₃ (aq) + AlCl₃ (aq) → Al(NO₃)₃ (aq) + 3AgCl (s) What mass in grams of AgCl is produced when 4.22 g of AgNO₃ react with 7.73 g of AlCl₃?

Under appropriate conditions, nitrogen and hydrogen undergo a combination reaction to yield ammonia: N₂ (g) + 3H₂ (g) → 2NH₃ (g) A 9.3-g sample of hydrogen requires ________ g of N₂ for a complete reaction.