Question 1

What is the Kelvin temperature at 24°C?

Accepted Answer

A)  249 K 
B)  11.4 K 
C)  -297 K 
D)  -249 K 
E)  297 K 
A)  249 K 
B)  11.4 K 
C)  -297 K 
D)  -249 K 
E)  297 K

Question 2

When active metals such as magnesium are immersed in acid solution, hydrogen gas is evolved. Calculate the volume of H2(g) at 30.1°C and 0.85 atm that can be formed when 275 mL of 0.725 M HCl solution reacts with excess Mg to give hydrogen gas and aqueous magnesium chloride. Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g)
(R = 0.08206 L • atm/K • mol)

Accepted Answer

A)  3.4 × 10-3 L 
B)  2.2 L 
C)  2.9 L 
D)  5.8 L 
E)  11.7 L 
A)  3.4 × 10-3 L 
B)  2.2 L 
C)  2.9 L 
D)  5.8 L 
E)  11.7 L

Question 3

STP stands for ________ _______ ________ ________.

Accepted Answer

standard t

Question 4

Suppose a sample of gas is composed of 100 molecules, with speeds given below.   According to the kinetic molecular theory, if the absolute temperature of the gas is halved, what is a reasonable estimation of the new distribution of speeds of the molecules?

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 5

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 6

Choose all answers that apply. Which of the following is/are characteristic(s) of gases?

Accepted Answer

A)  High compressibility 
B)  Has a static volume regardless of temperature and pressure 
C)  Formation of homogeneous mixtures regardless of the nature of gases 
D)  Relatively large distances between molecules 
E)  Always has a density of 1.00 gram per liter 
A)  High compressibility 
B)  Has a static volume regardless of temperature and pressure 
C)  Formation of homogeneous mixtures regardless of the nature of gases 
D)  Relatively large distances between molecules 
E)  Always has a density of 1.00 gram per liter

Question 7

Arrange the following gases in order of increasing rate of effusion: C2H6, Ar, HCl, and PH3.

Accepted Answer

A)  Ar < HCl<PH3 < C2H6 
B)  C2H6 < PH3 < HCl < Ar 
C)  Ar < PH3 < C2H6 < HCl 
D)  C2H6 < HCl < PH3 < Ar 
E)  Ar < PH3 < HCl < C2H6 
A)  Ar < HCl<PH3 < C2H6 
B)  C2H6 < PH3 < HCl < Ar 
C)  Ar < PH3 < C2H6 < HCl 
D)  C2H6 < HCl < PH3 < Ar 
E)  Ar < PH3 < HCl < C2H6

Question 8

What is the mass, in grams, of 2.74 L of CO gas measured at 33°C and 945 mmHg? (R = 0.08206 L • atm/mol • K, 1 atm = 760 mmHg)

Accepted Answer

A)  0.263 g 
B)  2.46 g 
C)  3.80 g 
D)  35.2 g 
E)  206 g 
A)  0.263 g 
B)  2.46 g 
C)  3.80 g 
D)  35.2 g 
E)  206 g

Question 9

A block of dry ice (solid CO2, density = 1.56 g/mL) of dimensions 25.0 cm × 25.0 cm × 25.0 cm is left to sublime (i.e., to pass from the solid phase to the gas phase) in a closed chamber of dimensions 4.00 m × 5.00 m × 3.00 m. Once the sublimation is complete, what is the partial pressure of carbon dioxide in the chamber at 25°C? (R = 0.08206 L • atm/K • mol, 1 atm = 760 mmHg)

Accepted Answer

A)  172 mmHg 
B)  107 mmHg 
C)  0.225 mmHg 
D)  0.172 mmHg 
E)  14.4 mmHg 
A)  172 mmHg 
B)  107 mmHg 
C)  0.225 mmHg 
D)  0.172 mmHg 
E)  14.4 mmHg

Question 10

According to the postulates of kinetic molecular theory, the molecules of all gases at a given temperature have the same average speed.

Accepted Answer

A) True 
 B)False

Question 11

Which of the following gases effuses most rapidly?

Accepted Answer

A)  nitrogen 
B)  oxygen 
C)  hydrogen chloride 
D)  ammonia 
E)  carbon monoxide 
A)  nitrogen 
B)  oxygen 
C)  hydrogen chloride 
D)  ammonia 
E)  carbon monoxide

Question 12

The pressure of hydrogen sulfide gas in a container is 3.565 ×104 Pa. What is this pressure in torr? (1 atm = 101,325 Pa = 760 torr)?

Accepted Answer

A)  46.91 torr 
B)  267.4 torr 
C)  351.8 torr 
D)  3612 torr 
E)  2.709 ×104 torr 
A)  46.91 torr 
B)  267.4 torr 
C)  351.8 torr 
D)  3612 torr 
E)  2.709 ×104 torr

Question 13

What is the final temperature of a gas that expands from a volume of 22.4 L at 278 K to a volume of 38.3 L at constant pressure?

Accepted Answer

A)  163 K 
B)  294 K 
C)  3.09 K 
D)  217 K 
E)  475 K 
A)  163 K 
B)  294 K 
C)  3.09 K 
D)  217 K 
E)  475 K

Question 14

If equal masses of O2(g) and HBr(g) are in separate containers of equal volume and temperature, which one of the following statements is true?

Accepted Answer

A)  The pressure in the O2 container is greater than that in the HBr container. 
B)  The average velocity of the O2 molecules is less than that of the HBr molecules. 
C)  The average kinetic energy of HBr molecules is greater than that of O2 molecules. 
D)  The pressures of both gases are the same. 
A)  The pressure in the O2 container is greater than that in the HBr container. 
B)  The average velocity of the O2 molecules is less than that of the HBr molecules. 
C)  The average kinetic energy of HBr molecules is greater than that of O2 molecules. 
D)  The pressures of both gases are the same.

Question 15

Select the gas with the highest average kinetic energy per mole at 298 K.

Accepted Answer

A)  O2 
B)  CO2 
C)  H2O 
D)  H2 
E)  All have the same average kinetic energy. 
A)  O2 
B)  CO2 
C)  H2O 
D)  H2 
E)  All have the same average kinetic energy.

Question 16

A gaseous compound is 30.4% nitrogen and 69.6% oxygen by mass. A 5.25-g sample of the gas occupies a volume of 1.00 L and exerts a pressure of 1.26 atm at -4.0°C. What is its molecular formula? (R = 0.08206 L • atm/K • mol)

Accepted Answer

A)  NO 
B)  NO2 
C)  N3O6 
D)  N2O4 
E)  N2O5 
A)  NO 
B)  NO2 
C)  N3O6 
D)  N2O4 
E)  N2O5

Question 17

Packaged cake mixes usually contain baking powder, a mixture of sodium hydrogen carbonate and calcium hydrogen phosphate that react to produce carbon dioxide gas when they come into contact with water. Many such mixes have special instructions for use at high altitudes. Why?

Accepted Answer

The baking powder acts as a le

What is the Kelvin temperature at 24°C?

STP stands for ____ _ __.

Suppose a sample of gas is composed of 100 molecules, with speeds given below. According to the kinetic molecular theory, if the absolute temperature of the gas is halved, what is a reasonable estimation of the new distribution of speeds of the molecules?

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)

Choose all answers that apply. Which of the following is/are characteristic(s) of gases?

Arrange the following gases in order of increasing rate of effusion: C₂H₆, Ar, HCl, and PH₃.

What is the mass, in grams, of 2.74 L of CO gas measured at 33°C and 945 mmHg? (R = 0.08206 L • atm/mol • K, 1 atm = 760 mmHg)

According to the postulates of kinetic molecular theory, the molecules of all gases at a given temperature have the same average speed.

Which of the following gases effuses most rapidly?

The pressure of hydrogen sulfide gas in a container is 3.565 ×10⁴ Pa. What is this pressure in torr? (1 atm = 101,325 Pa = 760 torr)?

What is the final temperature of a gas that expands from a volume of 22.4 L at 278 K to a volume of 38.3 L at constant pressure?

If equal masses of O₂(g) and HBr(g) are in separate containers of equal volume and temperature, which one of the following statements is true?

Select the gas with the highest average kinetic energy per mole at 298 K.

A gaseous compound is 30.4% nitrogen and 69.6% oxygen by mass. A 5.25-g sample of the gas occupies a volume of 1.00 L and exerts a pressure of 1.26 atm at -4.0°C. What is its molecular formula? (R = 0.08206 L • atm/K • mol)

Packaged cake mixes usually contain baking powder, a mixture of sodium hydrogen carbonate and calcium hydrogen phosphate that react to produce carbon dioxide gas when they come into contact with water. Many such mixes have special instructions for use at high altitudes. Why?

Chemistry: the Central Science

Atoms, Molecules, and Ions

Stoichiometry: Ratios of Combination

Reactions in Aqueous Solutions

Thermochemistry

Quantum Theory and the Electronic Structure of Atoms

Electron Configuration and the Periodic Table

Chemical Bonding I: Basic Concepts

Chemical Bonding II: Molecular Geometry and Bonding Theories

Intermolecular Forces and the Physical Properties of Liquids and Solids

Modern Materials

Physical Properties of Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Acid-Base Equilibria and Solubility Equilibria

Entropy, Free Energy, and Equilibrium

Electrochemistry

Nuclear Chemistry

Environmental Chemistry

Coordination Chemistry

Metallurgy and the Chemistry of Metals

Nonmetallic Elements and Their Compounds

Organic Chemistry

Filters

Exam 10: Gases

What is the Kelvin temperature at 24°C?

STP stands for ________ _______ ________ ________.

Suppose a sample of gas is composed of 100 molecules, with speeds given below. According to the kinetic molecular theory, if the absolute temperature of the gas is halved, what is a reasonable estimation of the new distribution of speeds of the molecules?

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)

Choose all answers that apply. Which of the following is/are characteristic(s) of gases?

Arrange the following gases in order of increasing rate of effusion: C2H6, Ar, HCl, and PH3.

What is the mass, in grams, of 2.74 L of CO gas measured at 33°C and 945 mmHg? (R = 0.08206 L • atm/mol • K, 1 atm = 760 mmHg)

According to the postulates of kinetic molecular theory, the molecules of all gases at a given temperature have the same average speed.

Which of the following gases effuses most rapidly?

The pressure of hydrogen sulfide gas in a container is 3.565 ×104 Pa. What is this pressure in torr? (1 atm = 101,325 Pa = 760 torr)?

What is the final temperature of a gas that expands from a volume of 22.4 L at 278 K to a volume of 38.3 L at constant pressure?

If equal masses of O2(g) and HBr(g) are in separate containers of equal volume and temperature, which one of the following statements is true?

Select the gas with the highest average kinetic energy per mole at 298 K.

A gaseous compound is 30.4% nitrogen and 69.6% oxygen by mass. A 5.25-g sample of the gas occupies a volume of 1.00 L and exerts a pressure of 1.26 atm at -4.0°C. What is its molecular formula? (R = 0.08206 L • atm/K • mol)

Packaged cake mixes usually contain baking powder, a mixture of sodium hydrogen carbonate and calcium hydrogen phosphate that react to produce carbon dioxide gas when they come into contact with water. Many such mixes have special instructions for use at high altitudes. Why?

Chemistry: the Central Science

Atoms, Molecules, and Ions

Stoichiometry: Ratios of Combination

Reactions in Aqueous Solutions

Thermochemistry

Quantum Theory and the Electronic Structure of Atoms

Electron Configuration and the Periodic Table

Chemical Bonding I: Basic Concepts

Chemical Bonding II: Molecular Geometry and Bonding Theories

Intermolecular Forces and the Physical Properties of Liquids and Solids

Modern Materials

Physical Properties of Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Acid-Base Equilibria and Solubility Equilibria

Entropy, Free Energy, and Equilibrium

Electrochemistry

Nuclear Chemistry

Environmental Chemistry

Coordination Chemistry

Metallurgy and the Chemistry of Metals

Nonmetallic Elements and Their Compounds

Organic Chemistry

Filters

STP stands for ____ _ __.

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)

Arrange the following gases in order of increasing rate of effusion: C₂H₆, Ar, HCl, and PH₃.

The pressure of hydrogen sulfide gas in a container is 3.565 ×10⁴ Pa. What is this pressure in torr? (1 atm = 101,325 Pa = 760 torr)?

If equal masses of O₂(g) and HBr(g) are in separate containers of equal volume and temperature, which one of the following statements is true?