Question 1

Determine the density of NH3 gas at 435 K and 1.00 bar.

Accepted Answer

A) 2.10 g L-1 
B) 0.471 g L-1 
C) 0.321 g L-1 
D) 2.24 g L-1 
E) 0.851 g L-1 
A) 2.10 g L-1 
B) 0.471 g L-1 
C) 0.321 g L-1 
D) 2.24 g L-1 
E) 0.851 g L-1

Question 2

Which of the following gases has the highest average speed at 400 K?

Accepted Answer

A) N2 
B) O2   
C) F2 
D) Cl2 
A) N2 
B) O2   
C) F2 
D) Cl2

Question 3

How many moles of an ideal gas are required to produce a pressure of 3.00 bar in a 1.50 L container with a temperature of 25.0 °C?

Accepted Answer

A) 0.146 
B) 0.0874 
C) 0.182 
D) 0.914 
E) 1.08 
A) 0.146 
B) 0.0874 
C) 0.182 
D) 0.914 
E) 1.08

Question 4

Convert 123.80 kPa to bar.

Accepted Answer

A) 1.222 bar 
B) 1.087 bar 
C) 0.8078 bar 
D) 0.9186 bar 
E) 1.238 bar 
A) 1.222 bar 
B) 1.087 bar 
C) 0.8078 bar 
D) 0.9186 bar 
E) 1.238 bar

Question 5

The density of a gas is 3.12 g L-1 at STP. What is the gas?

Accepted Answer

A) Cl2 
B) O3 
C) O2 
D) F2 
A) Cl2 
B) O3 
C) O2 
D) F2

Question 6

A sample of gas initially has a volume of 859 mL at 565 K and 2.20 bar. What pressure will the sample have if the volume changes to 268 mL while the temperature is increased to 815 K?

Accepted Answer

A) 10.2 bar 
B) 9.83 bar 
C) 15.3 bar 
D) 6.53 bar 
E) 1.05 bar 
A) 10.2 bar 
B) 9.83 bar 
C) 15.3 bar 
D) 6.53 bar 
E) 1.05 bar

Question 7

If CO2 and NH3 are allowed to effuse through a porous membrane under identical conditions, the rate of effusion for NH3 will be ________ times that of CO.

Accepted Answer

A) 0.39 
B) 0.62 
C) 1.6 
D) 2.6 
A) 0.39 
B) 0.62 
C) 1.6 
D) 2.6

Question 8

To what volume will a sample of gas expand if it is heated from 50.0 °C and 2.33 L to 500.0 °C?

Accepted Answer

A) 5.58 L 
B) 9.74 L 
C) 10.3 L 
D) 17.9 L 
E) 4.38 L 
A) 5.58 L 
B) 9.74 L 
C) 10.3 L 
D) 17.9 L 
E) 4.38 L

Question 9

What volume will 0.780 moles of He occupy at STP?

Accepted Answer

A) 22.4 L 
B) 70.0 L 
C) 43.7 L 
D) 17.7 L 
E) 15.6 L 
A) 22.4 L 
B) 70.0 L 
C) 43.7 L 
D) 17.7 L 
E) 15.6 L

Question 10

When 14.0 g of zinc metal reacts with excess HCl, how many litres of H2 gas are produced at STP? Zn(s)+ 2HCl(aq)→ ZnCl2(aq)+ H2(g)

Accepted Answer

A) 0.208 L 
B) 0.416 L 
C) 4.86 L 
D) 9.60 L 
A) 0.208 L 
B) 0.416 L 
C) 4.86 L 
D) 9.60 L

Question 11

Determine the mass of water formed when 12.5 L NH3 (at 298 K and 1.50 bar)is reacted with 18.9 L of O2 (at 323 K and 1.1 bar). 4NH3(g)+ 5O2(g)→ 4NO(g)+ 6H2O(g)

Accepted Answer

A) 16.7 g H2O 
B) 20.7 g H2O 
C) 37.7 g H2O 
D) 13.8 g H2O 
E) 27.9 g H2O 
A) 16.7 g H2O 
B) 20.7 g H2O 
C) 37.7 g H2O 
D) 13.8 g H2O 
E) 27.9 g H2O

Question 12

A sample of 0.300 moles of nitrogen occupies 0.600 L. Under the same conditions, what number of moles occupies 1.200 L?

Accepted Answer

A) 0.600 moles 
B) 1.50 moles 
C) 0.33 moles 
D) 6.00 moles 
A) 0.600 moles 
B) 1.50 moles 
C) 0.33 moles 
D) 6.00 moles

Question 13

A large balloon is initially filled to a volume of 25.0 L at 353 K and a pressure of 2575 mmHg. What volume of gas will the balloon contain at 1.368 bar and 253 K?

Accepted Answer

A) 22.2 L 
B) 87.5 L 
C) 11.4 L 
D) 45.0 L 
E) 58.6 L 
A) 22.2 L 
B) 87.5 L 
C) 11.4 L 
D) 45.0 L 
E) 58.6 L

Question 14

What is the Celsius temperature of 100.0 g of chlorine gas in a 55.0 L container at 1.069 bar?

Accepted Answer

A) -23°C 
B) 228°C 
C) 250°C 
D) 500°C 
A) -23°C 
B) 228°C 
C) 250°C 
D) 500°C

Question 15

Calculate the temperature if 3.120 moles of He has a pressure of 2.45 bar in a 23.8 L container.

Accepted Answer

A) 218 K 
B) 314 K 
C) 225 K 
D) 334 K 
E) 287 K 
A) 218 K 
B) 314 K 
C) 225 K 
D) 334 K 
E) 287 K

Question 16

What volume would 1.02 moles of Kr occupy at a pressure of 1.65 bar and a temperature of 281.2 K?

Accepted Answer

A) 28.7 L 
B) 14.5 L 
C) 12.7 L 
D) 6.87 L 
E) 16.9 L 
A) 28.7 L 
B) 14.5 L 
C) 12.7 L 
D) 6.87 L 
E) 16.9 L

Question 17

What mass of NO2 is contained in a 13.0 L tank at 4.58 bar and 385 K?

Accepted Answer

A) 18.8 g 
B) 53.1 g 
C) 24.4 g 
D) 85.6 g 
E) 69.2 g 
A) 18.8 g 
B) 53.1 g 
C) 24.4 g 
D) 85.6 g 
E) 69.2 g

Question 18

A gas is at 35.0 °C and 4.50 L. What is the temperature at 9.00 L?

Accepted Answer

A) 343°C 
B) 70.0°C 
C) 616°C 
D) 1.16°C 
E) 17.5°C 
A) 343°C 
B) 70.0°C 
C) 616°C 
D) 1.16°C 
E) 17.5°C

Question 19

The mole fraction of oxygen in dry air near sea level is 0.20948. The concentration of oxygen is ________ molecules per litre, assuming an atmospheric pressure of 0.985 bar and a temperature of 29.5 °C.

Accepted Answer

A) 6.23 
B) 0.00819 
C) 4.94 × 1021 
D) 3.75 × 1024 
E) 5.07 × 1022 
A) 6.23 
B) 0.00819 
C) 4.94 × 1021 
D) 3.75 × 1024 
E) 5.07 × 1022

Question 20

How many grams of calcium hydride are required to produce 4.56 L of hydrogen gas at 25.0 °C and 0.975 bar according to the chemical equation shown below? CaH2(s)+ 2H2O(l)→ Ca(OH)2(aq)+ 2H2(g)

Accepted Answer

A) 3.77 g 
B) 7.64 g 
C) 15.3 g 
D) 45.6 g 
A) 3.77 g 
B) 7.64 g 
C) 15.3 g 
D) 45.6 g

Exam 5: Gases

Determine the density of NH3 gas at 435 K and 1.00 bar.

Which of the following gases has the highest average speed at 400 K?

How many moles of an ideal gas are required to produce a pressure of 3.00 bar in a 1.50 L container with a temperature of 25.0 °C?

Convert 123.80 kPa to bar.

The density of a gas is 3.12 g L-1 at STP. What is the gas?

A sample of gas initially has a volume of 859 mL at 565 K and 2.20 bar. What pressure will the sample have if the volume changes to 268 mL while the temperature is increased to 815 K?

If CO2 and NH3 are allowed to effuse through a porous membrane under identical conditions, the rate of effusion for NH3 will be ________ times that of CO.

To what volume will a sample of gas expand if it is heated from 50.0 °C and 2.33 L to 500.0 °C?

What volume will 0.780 moles of He occupy at STP?

When 14.0 g of zinc metal reacts with excess HCl, how many litres of H2 gas are produced at STP? Zn(s)+ 2HCl(aq)→ ZnCl2(aq)+ H2(g)

Determine the mass of water formed when 12.5 L NH3 (at 298 K and 1.50 bar)is reacted with 18.9 L of O2 (at 323 K and 1.1 bar). 4NH3(g)+ 5O2(g)→ 4NO(g)+ 6H2O(g)

A sample of 0.300 moles of nitrogen occupies 0.600 L. Under the same conditions, what number of moles occupies 1.200 L?

A large balloon is initially filled to a volume of 25.0 L at 353 K and a pressure of 2575 mmHg. What volume of gas will the balloon contain at 1.368 bar and 253 K?

What is the Celsius temperature of 100.0 g of chlorine gas in a 55.0 L container at 1.069 bar?

Calculate the temperature if 3.120 moles of He has a pressure of 2.45 bar in a 23.8 L container.

What volume would 1.02 moles of Kr occupy at a pressure of 1.65 bar and a temperature of 281.2 K?

What mass of NO2 is contained in a 13.0 L tank at 4.58 bar and 385 K?

A gas is at 35.0 °C and 4.50 L. What is the temperature at 9.00 L?

The mole fraction of oxygen in dry air near sea level is 0.20948. The concentration of oxygen is ________ molecules per litre, assuming an atmospheric pressure of 0.985 bar and a temperature of 29.5 °C.

How many grams of calcium hydride are required to produce 4.56 L of hydrogen gas at 25.0 °C and 0.975 bar according to the chemical equation shown below? CaH2(s)+ 2H2O(l)→ Ca(OH)2(aq)+ 2H2(g)

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

Electrochemistry

Radioactivity and Nuclear Chemistry

Organic Chemistry I: Structures

Organic Chemistry II: Reactions

Biochemistry

Chemistry of the Nonmetals

Metals and Metallury

Transition Metals and Coordination Compounds

Filters

Determine the density of NH₃ gas at 435 K and 1.00 bar.

The density of a gas is 3.12 g L^-1 at STP. What is the gas?

If CO₂ and NH₃ are allowed to effuse through a porous membrane under identical conditions, the rate of effusion for NH₃ will be ________ times that of CO.

When 14.0 g of zinc metal reacts with excess HCl, how many litres of H₂ gas are produced at STP? Zn(s)+ 2HCl(aq)→ ZnCl₂(aq)+ H₂(g)

Determine the mass of water formed when 12.5 L NH₃ (at 298 K and 1.50 bar)is reacted with 18.9 L of O₂ (at 323 K and 1.1 bar). 4NH₃(g)+ 5O₂(g)→ 4NO(g)+ 6H₂O(g)

What mass of NO₂ is contained in a 13.0 L tank at 4.58 bar and 385 K?

How many grams of calcium hydride are required to produce 4.56 L of hydrogen gas at 25.0 °C and 0.975 bar according to the chemical equation shown below? CaH₂(s)+ 2H₂O(l)→ Ca(OH)₂(aq)+ 2H₂(g)