Question 1

How many grams of F2 gas are there in a 5.00 L cylinder at 5.327 bar and 23 °C?

Accepted Answer

A) 19.5 g 
B) 41.1 g 
C) 500 g 
D) 2.96 × 104 g 
A) 19.5 g 
B) 41.1 g 
C) 500 g 
D) 2.96 × 104 g

Question 2

Which of the following statements is TRUE?

Accepted Answer

A) At a given temperature, lighter gas particles travel more slowly than heavier gas particles. 
B) The smaller a gas particle, the slower it will effuse. 
C) The higher the temperature, the lower the average kinetic energy of the sample. 
D) At low temperatures, intermolecular forces become important and the pressure of a gas will be lower than predicted by the ideal gas law. 
E) None of the above statements is true. 
A) At a given temperature, lighter gas particles travel more slowly than heavier gas particles. 
B) The smaller a gas particle, the slower it will effuse. 
C) The higher the temperature, the lower the average kinetic energy of the sample. 
D) At low temperatures, intermolecular forces become important and the pressure of a gas will be lower than predicted by the ideal gas law. 
E) None of the above statements is true.

Question 3

How many millilitres of ozone gas at 25.0 °C and 1.00 bar are needed to react with 45.00 mL of a 0.100 mol L-1 aqueous solution of KI according to the chemical equation shown below?
O3(g)+ 2I-(aq)+ H2O(l)→ O2(g)+ I2(s)+ 2OH-(aq)

Accepted Answer

A) 54.8 mL 
B) 110 mL 
C) 165 mL 
D) 220 mL 
A) 54.8 mL 
B) 110 mL 
C) 165 mL 
D) 220 mL

Question 4

What volume will a balloon occupy at 1.01 bar if the balloon has a volume of 7.6 L at 3.85 bar?

Accepted Answer

A) 2.0 L 
B) 5.0 L 
C) 29 L 
D) 35 L 
E) 17 L 
A) 2.0 L 
B) 5.0 L 
C) 29 L 
D) 35 L 
E) 17 L

Question 5

To what temperature must a balloon, initially at 25 °C and 2.00 L, be heated to have a volume of 6.00 L?

Accepted Answer

A) 993 K 
B) 403 K 
C) 75 K 
D) 655 K 
E) 894 K 
A) 993 K 
B) 403 K 
C) 75 K 
D) 655 K 
E) 894 K

Question 6

Three identical flasks contain three different gases at standard temperature and pressure. Flask A contains C2H4 flask B contains O3, and flask C contains F2. Which flask contains the largest number of molecules?

Accepted Answer

A) flask A 
B) flask B 
C) flask C 
D) All contain the same number of molecules. 
A) flask A 
B) flask B 
C) flask C 
D) All contain the same number of molecules.

Question 7

What is the temperature if krypton has a root mean square velocity of 348 m s-1?

Accepted Answer

A) 800°C 
B) 791°C 
C) 134°C 
D) 604°C 
E) 596°C 
A) 800°C 
B) 791°C 
C) 134°C 
D) 604°C 
E) 596°C

Question 8

What pressure would a gas mixture in a 10.0 L tank exert if it were composed of 48.5 g He and 94.6 g CO2 at 398 K?

Accepted Answer

A) 7.11 bar 
B) 39.6 bar 
C) 40.1 bar 
D) 47.2 bar 
E) 58.7 bar 
A) 7.11 bar 
B) 39.6 bar 
C) 40.1 bar 
D) 47.2 bar 
E) 58.7 bar

Question 9

The density of a gas is 1.41 g L-1 at STP. What is the gas?

Accepted Answer

A) Cl2 
B) S 
C) O2 
D) Ne 
A) Cl2 
B) S 
C) O2 
D) Ne

Question 10

Determine the volume of H2S (at 375 K and 1.216 bar)needed to produce 55.0 g of S. Assume that there is excess SO2 present. 2H2S(g)+ SO2(g)→ 3S(s)+ 2H2O(g)

Accepted Answer

A) 44.0 L 
B) 29.3 L 
C) 22.7 L 
D) 34.1 L 
E) 66.0 L 
A) 44.0 L 
B) 29.3 L 
C) 22.7 L 
D) 34.1 L 
E) 66.0 L

Question 11

Identify the gas that is the lowest percent by volume in dry air.

Accepted Answer

A) CO2 
B) Ar 
C) O2 
D) N2 
A) CO2 
B) Ar 
C) O2 
D) N2

Question 12

Define pressure.

Accepted Answer

Pressure is the force exerted

Question 13

A mixture of He, Ne, and Ar has a pressure of 7.85 bar. If the Ne has a mole fraction of 0.47 and Ar has a mole fraction of 0.23, what is the pressure of He?

Accepted Answer

A) 4.2 bar 
B) 3.7 bar 
C) 1.8 bar 
D) 5.5 bar 
E) 2.4 bar 
A) 4.2 bar 
B) 3.7 bar 
C) 1.8 bar 
D) 5.5 bar 
E) 2.4 bar

Question 14

The following reaction is used to generate hydrogen gas in the laboratory. If 243 mL of gas is collected at 25 °C and has a total pressure of 0.9933 bar, what mass of hydrogen is produced? A possibly useful table of water vapour pressures is provided below. Mg(s)+ 2HCl(aq)→ MgCl2(aq)+ H2(g) T (°C)P (bar)
20 0.023398
25 0.031704
30 0.042477

Accepted Answer

A) 0.0196 g H2 
B) 0.0717 g H2 
C) 0.0190 g H2 
D) 0.0144 g H2 
E) 0.0449 g H2 
A) 0.0196 g H2 
B) 0.0717 g H2 
C) 0.0190 g H2 
D) 0.0144 g H2 
E) 0.0449 g H2

Question 15

Why does hot air rise?

Accepted Answer

As air is heated, it expands a

Question 16

What is the lowest layer of the atmosphere?

Accepted Answer

A) stratosphere 
B) mesosphere 
C) nanosphere 
D) troposphere 
E) thermosphere 
A) stratosphere 
B) mesosphere 
C) nanosphere 
D) troposphere 
E) thermosphere

Question 17

What is the pressure in a gas container that is connected to an open-end U-tube manometer if the pressure of the atmosphere is 742 Torr and the level of mercury in the arm connected to the container is 8.60 cm higher than the level of mercury open to the atmosphere?

Accepted Answer

A) 656 mmHg 
B) 733 mmHg 
C) 751 mmHg 
D) 828 mmHg 
A) 656 mmHg 
B) 733 mmHg 
C) 751 mmHg 
D) 828 mmHg

Question 18

What pressure will 2.6 × 1023 molecules of H2 exert in a 3.9 L container at 45 °C?

Accepted Answer

A) 5.7 bar 
B) 1.7 bar 
C) 2.9 bar 
D) 3.4 bar 
E) 4.6 bar 
A) 5.7 bar 
B) 1.7 bar 
C) 2.9 bar 
D) 3.4 bar 
E) 4.6 bar

Question 19

Which of the following gas samples would be most likely to behave ideally under the stated conditions?

Accepted Answer

A) Ne at STP 
B) CO at 200 bar and 25 °C 
C) SO2 at 2 bar and 0 K 
D) N2 at 1 bar and -70 °C 
E) O2 at 400 bar and 25 °C 
A) Ne at STP 
B) CO at 200 bar and 25 °C 
C) SO2 at 2 bar and 0 K 
D) N2 at 1 bar and -70 °C 
E) O2 at 400 bar and 25 °C

Question 20

How many molecules of N2 are in a 400.0 mL container at 1.0399 bar and 135 °C?

Accepted Answer

A) 7.01 × 1021 molecules 
B) 7.38 × 1021 molecules 
C) 2.12 × 1022 molecules 
D) 2.23 × 1022 molecules 
A) 7.01 × 1021 molecules 
B) 7.38 × 1021 molecules 
C) 2.12 × 1022 molecules 
D) 2.23 × 1022 molecules

Exam 5: Gases

How many grams of F2 gas are there in a 5.00 L cylinder at 5.327 bar and 23 °C?

Which of the following statements is TRUE?

How many millilitres of ozone gas at 25.0 °C and 1.00 bar are needed to react with 45.00 mL of a 0.100 mol L-1 aqueous solution of KI according to the chemical equation shown below? O3(g)+ 2I-(aq)+ H2O(l)→ O2(g)+ I2(s)+ 2OH-(aq)

What volume will a balloon occupy at 1.01 bar if the balloon has a volume of 7.6 L at 3.85 bar?

To what temperature must a balloon, initially at 25 °C and 2.00 L, be heated to have a volume of 6.00 L?

Three identical flasks contain three different gases at standard temperature and pressure. Flask A contains C2H4 flask B contains O3, and flask C contains F2. Which flask contains the largest number of molecules?

What is the temperature if krypton has a root mean square velocity of 348 m s-1?

What pressure would a gas mixture in a 10.0 L tank exert if it were composed of 48.5 g He and 94.6 g CO2 at 398 K?

The density of a gas is 1.41 g L-1 at STP. What is the gas?

Determine the volume of H2S (at 375 K and 1.216 bar)needed to produce 55.0 g of S. Assume that there is excess SO2 present. 2H2S(g)+ SO2(g)→ 3S(s)+ 2H2O(g)

Identify the gas that is the lowest percent by volume in dry air.

Define pressure.

A mixture of He, Ne, and Ar has a pressure of 7.85 bar. If the Ne has a mole fraction of 0.47 and Ar has a mole fraction of 0.23, what is the pressure of He?

Why does hot air rise?

What is the lowest layer of the atmosphere?

What is the pressure in a gas container that is connected to an open-end U-tube manometer if the pressure of the atmosphere is 742 Torr and the level of mercury in the arm connected to the container is 8.60 cm higher than the level of mercury open to the atmosphere?

What pressure will 2.6 × 1023 molecules of H2 exert in a 3.9 L container at 45 °C?

Which of the following gas samples would be most likely to behave ideally under the stated conditions?

How many molecules of N2 are in a 400.0 mL container at 1.0399 bar and 135 °C?

Units of Measurement for Physical and Chemical Change

Atoms and Elements

Molecules, Compounds, and Nomenclature

Chemical Reactions and Stoichiometry

Thermochemistry

The Quantum-Mechanical Model of the Atom

Periodic Properties of the Elements

Chemical Bonding I: Lewis Theory

Chemical Bonding Ii: Molecular Shapes, Valence Bond Theory, and Molecular Orbital Theory

Liquids, Solids, and Intermolecular Forces

Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Aqueous Ionic Equilibrium

Gibbs Energy and Thermodynamics

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Radioactivity and Nuclear Chemistry

Organic Chemistry I: Structures

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Chemistry of the Nonmetals

Metals and Metallury

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Filters

How many grams of F₂ gas are there in a 5.00 L cylinder at 5.327 bar and 23 °C?

How many millilitres of ozone gas at 25.0 °C and 1.00 bar are needed to react with 45.00 mL of a 0.100 mol L^-1 aqueous solution of KI according to the chemical equation shown below? O₃(g)+ 2I^-(aq)+ H₂O(l)→ O₂(g)+ I₂(s)+ 2OH^-(aq)

Three identical flasks contain three different gases at standard temperature and pressure. Flask A contains C₂H₄ flask B contains O₃, and flask C contains F₂. Which flask contains the largest number of molecules?

What is the temperature if krypton has a root mean square velocity of 348 m s^-1?

What pressure would a gas mixture in a 10.0 L tank exert if it were composed of 48.5 g He and 94.6 g CO₂ at 398 K?

The density of a gas is 1.41 g L^-1 at STP. What is the gas?

Determine the volume of H₂S (at 375 K and 1.216 bar)needed to produce 55.0 g of S. Assume that there is excess SO₂ present. 2H₂S(g)+ SO₂(g)→ 3S(s)+ 2H₂O(g)

What pressure will 2.6 × 10²³ molecules of H₂ exert in a 3.9 L container at 45 °C?

How many molecules of N₂ are in a 400.0 mL container at 1.0399 bar and 135 °C?