Question 1

To what volume will a 2.33 L sample of gas expand if it is heated from 30.0°C to 300.0°C?

Accepted Answer

A)  4.41 L 
B)  23.3 L 
C)  0.233 L 
D)  1.23 L 
E)  0.812 L 
A)  4.41 L 
B)  23.3 L 
C)  0.233 L 
D)  1.23 L 
E)  0.812 L A

Question 2

The mole fraction of argon in dry air near sea level is 1.819 × 10-5 where the molar mass of argon is 39.948.The concentration of argon in the atmosphere is ________%.

Accepted Answer

A)  7.23 × 10-5 
B)  1.819 × 10-5 
C)  9.09 × 106 
D)  1.819 × 10-3 
E)  9.09 × 10-5 
A)  7.23 × 10-5 
B)  1.819 × 10-5 
C)  9.09 × 106 
D)  1.819 × 10-3 
E)  9.09 × 10-5 D

Question 3

The action of some commercial drain cleaners is based on the following reaction: 2 NaOH(s)+ 2 Al(s)+ 6 H2O(l)→ 2 NaAl(OH)4(s)+ 3 H2(g)
What is the volume of H2 gas formed at STP when 4.32 g of Al reacts with excess NaOH?

Accepted Answer

A)  2.39 L 
B)  3.59 L 
C)  5.38 L 
D)  5.88 L 
A)  2.39 L 
B)  3.59 L 
C)  5.38 L 
D)  5.88 L C

Question 4

A 0.529-g sample of gas occupies 125 mL at 60.cm of Hg and 25°C.What is the molar mass of the gas?

Accepted Answer

A)  11 g/mol 
B)  81 g/mol 
C)  110 g/mol 
D)  130 g/mol 
A)  11 g/mol 
B)  81 g/mol 
C)  110 g/mol 
D)  130 g/mol

Question 5

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 752 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)  666 mm Hg 
B)  743 mm Hg 
C)  761 mm Hg 
D)  838 mm Hg 
A)  666 mm Hg 
B)  743 mm Hg 
C)  761 mm Hg 
D)  838 mm Hg

Question 6

Give the definition for diffusion.

Accepted Answer

A)  gas molecules mix equally 
B)  gas molecules spread out in response to a concentration gradient 
C)  gas molecules escape from a container into a vacuum through a small hole 
D)  average distance between collisions 
E)  gas molecules mix unequally 
A)  gas molecules mix equally 
B)  gas molecules spread out in response to a concentration gradient 
C)  gas molecules escape from a container into a vacuum through a small hole 
D)  average distance between collisions 
E)  gas molecules mix unequally

Question 7

Why does the rate of effusion increase with a decrease in the molar mass?

Accepted Answer

The rate of effusion depends on the spee

Question 8

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

Accepted Answer

A)  He at STP 
B)  CO at 200 atm and 25°C 
C)  SO2 at 2 atm and 0 K 
D)  Cl2 at 1 atm and -70°C 
E)  O2 at 400 atm and 25°C 
A)  He at STP 
B)  CO at 200 atm and 25°C 
C)  SO2 at 2 atm and 0 K 
D)  Cl2 at 1 atm and -70°C 
E)  O2 at 400 atm and 25°C

Question 9

The volume of a gas is inversely proportional to the pressure of a gas is known as

Accepted Answer

A)  Avogadro's Law. 
B)  Ideal Gas Law. 
C)  Charles's Law. 
D)  Boyle's Law. 
E)  Dalton's Law. 
A)  Avogadro's Law. 
B)  Ideal Gas Law. 
C)  Charles's Law. 
D)  Boyle's Law. 
E)  Dalton's Law.

Question 10

Calculate the temperature,in K,of 2.20 moles of gas occupying 3.70 L at 3.12 atm.

Accepted Answer

A)  64.0 K 
B)  -209 K 
C)  337 K 
D)  28.0 K 
A)  64.0 K 
B)  -209 K 
C)  337 K 
D)  28.0 K

Question 11

A sample of 0.400 moles of nitrogen occupies 0.800 L.Under the same conditions,what number of moles occupies 1.200 L?

Accepted Answer

A)  0.600 moles 
B)  0.417 moles 
C)  2.40 moles 
D)  0.216 moles 
A)  0.600 moles 
B)  0.417 moles 
C)  2.40 moles 
D)  0.216 moles

Question 12

Identify the element or molecule that has the lowest effusion rate.

Accepted Answer

A)  He  
B)  N2 
C)  NO2 
D)  Cl2 
E)  Xe 
A)  He  
B)  N2 
C)  NO2 
D)  Cl2 
E)  Xe

Question 13

In Lhasa,Tibet,the elevation is 12,000 feet.The altimeter reading in an airplane is 19.00 in Hg.This pressure is equal to ________ torr.

Accepted Answer

A)  9.33 
B)  483 
C)  0.635 
D)  1.57 
E)  23.1 
A)  9.33 
B)  483 
C)  0.635 
D)  1.57 
E)  23.1

Question 14

How many grams of NO gas are there in a 5.00-L cylinder at 4.00 × 103 mm Hg and 23°C?

Accepted Answer

A)  13.9 g 
B)  32.5 g 
C)  417 g 
D)  2.47 × 104 g 
A)  13.9 g 
B)  32.5 g 
C)  417 g 
D)  2.47 × 104 g

Question 15

Calculate the root mean square velocity of nitrogen molecules at 25°C.

Accepted Answer

A)  729 m/s 
B)  515 m/s 
C)  149 m/s 
D)  297 m/s 
A)  729 m/s 
B)  515 m/s 
C)  149 m/s 
D)  297 m/s

Question 16

Determine the density of N2 gas at STP.

Accepted Answer

A)  1.25 g/L 
B)  3.50 g/L 
C)  0.66 g/L 
D)  6.44 g/L 
E)  7.50 g/L 
A)  1.25 g/L 
B)  3.50 g/L 
C)  0.66 g/L 
D)  6.44 g/L 
E)  7.50 g/L

Question 17

A syringe initially holds a sample of gas with a volume of 285 mL at 355 K and 1.88 atm.To what temperature must the gas in the syringe be heated/cooled in order to have a volume of 435 mL at 2.50 atm?

Accepted Answer

A)  139 K 
B)  572 K 
C)  175 K 
D)  466 K 
E)  721 K 
A)  139 K 
B)  572 K 
C)  175 K 
D)  466 K 
E)  721 K

Question 18

When 15.0 g of zinc metal reacts with excess HCl,how many liters of H2 gas are produced at STP?

Accepted Answer

A)  0.229 L 
B)  0.458 L 
C)  5.14 L 
D)  10.3 L 
A)  0.229 L 
B)  0.458 L 
C)  5.14 L 
D)  10.3 L

Question 19

How many molecules of N2 are contained in a 10.0 L tank at 7.53 atm and 485 K?

Accepted Answer

A)  1.89 × 1024 molecules 
B)  1.14 × 1024 molecules 
C)  8.32 × 1024 molecules 
D)  4.89 × 1024 molecules 
E)  3.63 × 1024 molecules 
A)  1.89 × 1024 molecules 
B)  1.14 × 1024 molecules 
C)  8.32 × 1024 molecules 
D)  4.89 × 1024 molecules 
E)  3.63 × 1024 molecules

Question 20

Identify the element or molecule that has the highest diffusion rate.

Accepted Answer

A)  H2 
B)  N2 
C)  Ar  
D)  Cl2 
E)  Rn 
A)  H2 
B)  N2 
C)  Ar  
D)  Cl2 
E)  Rn

Exam 5: Gases

To what volume will a 2.33 L sample of gas expand if it is heated from 30.0°C to 300.0°C?

The mole fraction of argon in dry air near sea level is 1.819 × 10-5 where the molar mass of argon is 39.948.The concentration of argon in the atmosphere is ________%.

The action of some commercial drain cleaners is based on the following reaction: 2 NaOH(s)+ 2 Al(s)+ 6 H2O(l)→ 2 NaAl(OH)4(s)+ 3 H2(g) What is the volume of H2 gas formed at STP when 4.32 g of Al reacts with excess NaOH?

A 0.529-g sample of gas occupies 125 mL at 60.cm of Hg and 25°C.What is the molar mass of the gas?

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 752 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?

Give the definition for diffusion.

Why does the rate of effusion increase with a decrease in the molar mass?

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

The volume of a gas is inversely proportional to the pressure of a gas is known as

Calculate the temperature,in K,of 2.20 moles of gas occupying 3.70 L at 3.12 atm.

A sample of 0.400 moles of nitrogen occupies 0.800 L.Under the same conditions,what number of moles occupies 1.200 L?

Identify the element or molecule that has the lowest effusion rate.

In Lhasa,Tibet,the elevation is 12,000 feet.The altimeter reading in an airplane is 19.00 in Hg.This pressure is equal to ________ torr.

How many grams of NO gas are there in a 5.00-L cylinder at 4.00 × 103 mm Hg and 23°C?

Calculate the root mean square velocity of nitrogen molecules at 25°C.

Determine the density of N2 gas at STP.

A syringe initially holds a sample of gas with a volume of 285 mL at 355 K and 1.88 atm.To what temperature must the gas in the syringe be heated/cooled in order to have a volume of 435 mL at 2.50 atm?

When 15.0 g of zinc metal reacts with excess HCl,how many liters of H2 gas are produced at STP?

How many molecules of N2 are contained in a 10.0 L tank at 7.53 atm and 485 K?

Identify the element or molecule that has the highest diffusion rate.

Matter, measurement, and Problem Solving

Atoms and Elements

Molecules,compounds,and Chemical Equations

Chemical Quantities and Aqueous Reactions

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,

Liquids,solids,and Intermolecular Forces

Solids and Modern Materials

Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Aqueous Ionic Equilibrium

Free Energy and Thermodynamics

Electrochemistry

Radioactivity and Nuclear Chemistry

Organic Chemistry

Biochemistry

Chemistry of the Nonmetals

Metals and Metallurgy

Transition Metals and Coordination Compounds

Filters

The mole fraction of argon in dry air near sea level is 1.819 × 10^-5 where the molar mass of argon is 39.948.The concentration of argon in the atmosphere is ________%.

The action of some commercial drain cleaners is based on the following reaction: 2 NaOH(s)+ 2 Al(s)+ 6 H₂O(l)→ 2 NaAl(OH)₄(s)+ 3 H₂(g) What is the volume of H₂ gas formed at STP when 4.32 g of Al reacts with excess NaOH?

How many grams of NOgas are there in a 5.00-L cylinder at 4.00 × 10³ mm Hg and 23°C?

Determine the density of N₂ gas at STP.

When 15.0 g of zinc metal reacts with excess HCl,how many liters of H₂ gas are produced at STP?

How many molecules of N₂ are contained in a 10.0 L tank at 7.53 atm and 485 K?