Question 1

A sample of helium gas occupies 355mL at 23°C.If the container the He is in is expanded to 1.50 L at constant pressure, what is the final temperature for the He at this new volume?

Accepted Answer

A) 1,250 °C 
B) 978 °C 
C) 70.1 °C 
D) 80.0 °C 
E) 1,520 °C 
A) 1,250 °C 
B) 978 °C 
C) 70.1 °C 
D) 80.0 °C 
E) 1,520 °C B

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.

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 C

Question 3

The mole fraction of oxygen molecules in dry air is 0.2095.What volume of dry air at 1.00 atm and 25°C is required for burning 1.00 L of hexane (C6H14, density = 0.660 g/mL)completely, yielding carbon dioxide and water?

Accepted Answer

A) 187 L 
B) 712 L 
C) 894 L 
D) 1780 L 
E) 8490 L 
A) 187 L 
B) 712 L 
C) 894 L 
D) 1780 L 
E) 8490 L E

Question 4

What volume of O2(g)at 810.mmHg pressure is required to react completely with a 4.50g sample of C(s)at 48°C? 2 C(s)+ O2(g)$\rarr$ 2 CO(g)

Accepted Answer

A) 1.22 L 
B) 3.47 L 
C) 4.63 L 
D) 9.26 L 
E) 111 L 
A) 1.22 L 
B) 3.47 L 
C) 4.63 L 
D) 9.26 L 
E) 111 L

Question 5

Which of these properties is/are characteristic(s)of gases?

Accepted Answer

A) High compressibility 
B) Relatively large distances between molecules 
C) Formation of homogeneous mixtures regardless of the nature of gases 
D) A and B. 
E) A, B, and C. 
A) High compressibility 
B) Relatively large distances between molecules 
C) Formation of homogeneous mixtures regardless of the nature of gases 
D) A and B. 
E) A, B, and C.

Question 6

How many atoms of He gas are present in a 450 mL container at 35°C and 740 mmHg?

Accepted Answer

A) 0.017 He atoms 
B) 0.068 He atoms 
C) 1.2 x 105 He atoms 
D) 1.0 x 1022 He atoms 
E) 7.9 x 1024 He atoms 
A) 0.017 He atoms 
B) 0.068 He atoms 
C) 1.2 x 105 He atoms 
D) 1.0 x 1022 He atoms 
E) 7.9 x 1024 He atoms

Question 7

Which of the following describes Dalton's Law?

Accepted Answer

A) The pressure of a gas is proportional to its volume 
B) The total pressure of a gas mixture is the sum of the partial pressures of each gas in the mixture 
C) The temperature of a gas is proportional to its volume 
D) Only one variable can be changed from an initial state to a final state for a gas 
A) The pressure of a gas is proportional to its volume 
B) The total pressure of a gas mixture is the sum of the partial pressures of each gas in the mixture 
C) The temperature of a gas is proportional to its volume 
D) Only one variable can be changed from an initial state to a final state for a gas

Question 8

Calculate the molar mass of a gaseous substance if 0.125 g of the gas occupies 93.3 mL at STP.

Accepted Answer

The answer of Calculate the molar mass of a gaseous...

Question 9

What is standard temperature and standard pressure in units of °C and atm?

Accepted Answer

0°C and 1

Question 10

Calculate the volume occupied by 56.5 g of argon gas at STP.

Accepted Answer

A) 22.4 L 
B) 31.7 L 
C) 34.6 L 
D) 1,270 L 
E) 1,380 L 
A) 22.4 L 
B) 31.7 L 
C) 34.6 L 
D) 1,270 L 
E) 1,380 L

Question 11

A gas evolved during the fermentation of sugar was collected.After purification its volume was found to be 25.0 L at 22.5°C and 702 mmHg.How many moles of gas were collected?

Accepted Answer

A) 0.95 mol 
B) 1.05 mol 
C) 12.5 mol 
D) 22.4 mol 
E) 724 mol 
A) 0.95 mol 
B) 1.05 mol 
C) 12.5 mol 
D) 22.4 mol 
E) 724 mol

Question 12

The following data describes an initial and final state for an ideal gas.Given that the amount of gas does not change in the process, what is the final pressure (atm)of the gas?

Accepted Answer

The answer of The following data describes an initial and...

Question 13

What is the definition of a "gas"?

Accepted Answer

A "gas" is a substance in whic

Question 14

What is the molar mass of Freon-11 gas if its density is 6.13 g/L at STP?

Accepted Answer

A) 0.274 g/mol 
B) 3.64 g/mol 
C) 78.2 g/mol 
D) 137 g/mol 
E) 365 g/mol 
A) 0.274 g/mol 
B) 3.64 g/mol 
C) 78.2 g/mol 
D) 137 g/mol 
E) 365 g/mol

Question 15

A sample of pure nitrogen has a temperature of 15 °C.What is the temperature of the nitrogen in units of Kelvin?

Accepted Answer

A) 300 K 
B) 290 K 
C) 288 K 
D) 288.2 K 
E) 288.15 K 
A) 300 K 
B) 290 K 
C) 288 K 
D) 288.2 K 
E) 288.15 K

Question 16

What is the pressure (in atmospheres)of the sample of gas trapped in the open-tube mercury manometer shown below if atmospheric pressure is 735 mmHg and h = 8.3 cm?

Accepted Answer

The answer of What is the pressure (in atmospheres)of the...

Question 17

Calculate the density, in g/L, of SF6 gas at 27°C and 0.500 atm pressure.

Accepted Answer

A) 3.38 × 10-3 g/L 
B) 2.96 g/L 
C) 22.4 g/L 
D) 32.9 g/L 
E) 3.38 kg/L 
A) 3.38 × 10-3 g/L 
B) 2.96 g/L 
C) 22.4 g/L 
D) 32.9 g/L 
E) 3.38 kg/L

Question 18

Give five examples (list names)of compounds that exist as gases at room temperature and pressure.

Accepted Answer

(Answers will vary.)

Question 19

Gasoline (which can be considered to be octane, C8H18)burns in oxygen to produce carbon dioxide and water.What volume (L)of oxygen at STP is necessary to react with 1.0 gal of gasoline?
(The density of gasoline is 0.81 g/mL.1 gal = 3.78 L)

Accepted Answer

Question 20

What is the pressure of the gas trapped in the apparatus shown below when the atmospheric pressure is 720 mmHg?

Accepted Answer

A) 12 mmHg 
B) 708 mmHg 
C) 720 mmHg 
D) 732 mmHg 
E) 760 mmHg 
A) 12 mmHg 
B) 708 mmHg 
C) 720 mmHg 
D) 732 mmHg 
E) 760 mmHg

Exam 5: Gases

A sample of helium gas occupies 355mL at 23°C.If the container the He is in is expanded to 1.50 L at constant pressure, what is the final temperature for the He at this new volume?

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.

The mole fraction of oxygen molecules in dry air is 0.2095.What volume of dry air at 1.00 atm and 25°C is required for burning 1.00 L of hexane (C6H14, density = 0.660 g/mL)completely, yielding carbon dioxide and water?

What volume of O2(g)at 810.mmHg pressure is required to react completely with a 4.50g sample of C(s)at 48°C? 2 C(s)+ O2(g) →\rarr→ 2 CO(g)

Which of these properties is/are characteristic(s)of gases?

How many atoms of He gas are present in a 450 mL container at 35°C and 740 mmHg?

Which of the following describes Dalton's Law?

Calculate the molar mass of a gaseous substance if 0.125 g of the gas occupies 93.3 mL at STP.

What is standard temperature and standard pressure in units of °C and atm?

Calculate the volume occupied by 56.5 g of argon gas at STP.

A gas evolved during the fermentation of sugar was collected.After purification its volume was found to be 25.0 L at 22.5°C and 702 mmHg.How many moles of gas were collected?

The following data describes an initial and final state for an ideal gas.Given that the amount of gas does not change in the process, what is the final pressure (atm)of the gas?

What is the definition of a "gas"?

What is the molar mass of Freon-11 gas if its density is 6.13 g/L at STP?

A sample of pure nitrogen has a temperature of 15 °C.What is the temperature of the nitrogen in units of Kelvin?

What is the pressure (in atmospheres)of the sample of gas trapped in the open-tube mercury manometer shown below if atmospheric pressure is 735 mmHg and h = 8.3 cm?

Calculate the density, in g/L, of SF6 gas at 27°C and 0.500 atm pressure.

Give five examples (list names)of compounds that exist as gases at room temperature and pressure.

Gasoline (which can be considered to be octane, C8H18)burns in oxygen to produce carbon dioxide and water.What volume (L)of oxygen at STP is necessary to react with 1.0 gal of gasoline? (The density of gasoline is 0.81 g/mL.1 gal = 3.78 L)

What is the pressure of the gas trapped in the apparatus shown below when the atmospheric pressure is 720 mmHg?

Chemistry: the Study of Change

Atoms, Molecules, and Ions

Mass Relationships in Chemical Reactions

Reactions in Aqueous Solutions

Thermochemistry

Quantum Theory and the Electronic Structure of Atoms

Periodic Relationships Among the Elements

Chemical Bonding I: Basic Concepts

Chemical Bonding Ii: Molecular Geometry and Hybridization of Atomic Orbitals

Intermolecular Forces and Liquids and Solids

Physical Properties of Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Acid-Base Equilibria and Solubility Equilibria

Entropy Free Energy and Equilibrium

Electrochemistry

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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.

The mole fraction of oxygen molecules in dry air is 0.2095.What volume of dry air at 1.00 atm and 25°C is required for burning 1.00 L of hexane (C₆H₁₄, density = 0.660 g/mL)completely, yielding carbon dioxide and water?

What volume of O₂(g)at 810.mmHg pressure is required to react completely with a 4.50g sample of C(s)at 48°C? 2 C(s)+ O₂(g) $\rarr$ 2 CO(g)

Calculate the density, in g/L, of SF₆ gas at 27°C and 0.500 atm pressure.

Gasoline (which can be considered to be octane, C₈H₁₈)burns in oxygen to produce carbon dioxide and water.What volume (L)of oxygen at STP is necessary to react with 1.0 gal of gasoline? (The density of gasoline is 0.81 g/mL.1 gal = 3.78 L)