Question 1

For an ideal gas, a plot of PV/nRT versus P gives a straight line with a positive slope.

Accepted Answer

A) True 
 B)False  False

Question 2

"The pressure of an ideal gas is directly proportional to its absolute temperature at constant volume and number of moles" is a statement of ________________ Law.

Accepted Answer

A)  Charles's 
B)  Boyle's 
C)  Amontons's 
D)  Avogadro's 
E)  Gay-Lussac's 
A)  Charles's 
B)  Boyle's 
C)  Amontons's 
D)  Avogadro's 
E)  Gay-Lussac's C

Question 3

A sample of nitrogen gas is confined to a 14.0 L container at 375 torr and 37.0$\degree$C. How many moles of nitrogen are in the container?

Accepted Answer

A)  0.271 mol 
B)  2.27 mol 
C)  3.69 mol 
D)  206 mol 
E)  227 mol 
A)  0.271 mol 
B)  2.27 mol 
C)  3.69 mol 
D)  206 mol 
E)  227 mol A

Question 4

A sample of methane gas, CH4(g), occupies a volume of 60.3 L at a pressure of 469 torr and a temperature of 29.3$\degree$C. What would be its temperature at a pressure of 243 torr and volume of 60.3 L?

Accepted Answer

A)  -116.5$\degree$C 
B)  15.2 $\degree$C 
C)  15.5$\degree$C 
D)  57.7$\degree$C 
E)  310.6$\degree$C 
A)  -116.5$\degree$C 
B)  15.2 $\degree$C 
C)  15.5$\degree$C 
D)  57.7$\degree$C 
E)  310.6$\degree$C

Question 5

A flask containing neon gas is connected to an open-ended mercury manometer. The open end is exposed to the atmosphere, where the prevailing pressure is 745 torr. The mercury level in the open arm is 50. mm below that in the arm connected to the flask of neon. What is the neon pressure, in torr?

Accepted Answer

A)  -50. torr 
B)  50. torr 
C)  695 torr 
D)  795 torr 
E)  None of these choices is correct. 
A)  -50. torr 
B)  50. torr 
C)  695 torr 
D)  795 torr 
E)  None of these choices is correct.

Question 6

Methane, CH4(g), reacts with steam to give synthesis gas, a mixture of carbon monoxide and hydrogen, which is used as starting material for the synthesis of a number of organic and inorganic compounds. 
CH4(g) + H2O(g) $\rightarrow$ CO(g) + H2(g) [unbalanced]
What mass of hydrogen is formed if 275 L of methane (measured at STP) is converted to synthesis gas?

Accepted Answer

A)  12.3 g 
B)  24.7 g 
C)  37.1 g 
D)  49.4 g 
E)  74.2 g 
A)  12.3 g 
B)  24.7 g 
C)  37.1 g 
D)  49.4 g 
E)  74.2 g

Question 7

At a temperature of absolute zero, the volume of an ideal gas is zero.

Accepted Answer

A) True 
 B)False

Question 8

Calculate the root-mean-square speed of methane, CH4 (g), at 78$\degree$C.

Accepted Answer

A)  23 m/s 
B)  350 m/s 
C)  550 m/s 
D)  667 m/s 
E)  740 m/s 
A)  23 m/s 
B)  350 m/s 
C)  550 m/s 
D)  667 m/s 
E)  740 m/s

Question 9

An unknown liquid is vaporized in a 273-mL flask by immersion in a water bath at 99$\degree$C. The barometric pressure is 753 torr. If the mass of the vapor retained in the flask is 1.362 g, what is its molar mass?

Accepted Answer

A)  20.4 g/mol 
B)  40.9 g/mol 
C)  112 g/mol 
D)  154 g/mol 
E)  184 g/mol 
A)  20.4 g/mol 
B)  40.9 g/mol 
C)  112 g/mol 
D)  154 g/mol 
E)  184 g/mol

Question 10

Mercury is 13.6 times as dense as liquid water. What would be the reading of a water-filled barometer at normal atmospheric pressure, 760. mmHg?

Accepted Answer

A)  1.03 * 103 torr 
B)  1.03 * 103 Pa 
C)  1.03 * 103 mm height of water column 
D)  1.03 * 103 cm height of water column 
E)  13.6 atm 
A)  1.03 * 103 torr 
B)  1.03 * 103 Pa 
C)  1.03 * 103 mm height of water column 
D)  1.03 * 103 cm height of water column 
E)  13.6 atm

Question 11

A 750-mL sample of hydrogen exerts a pressure of 822 torr at 325 K. What pressure does it exert if the temperature is raised to 475 K at constant volume?

Accepted Answer

A)  188 torr 
B)  562 torr 
C)  1.11 * 103 torr 
D)  1.20 * 103 torr 
E)  1.90 * 103 torr 
A)  188 torr 
B)  562 torr 
C)  1.11 * 103 torr 
D)  1.20 * 103 torr 
E)  1.90 * 103 torr

Question 12

A flask containing helium gas is connected to an open-ended mercury manometer. The open end is exposed to the atmosphere, where the prevailing pressure is 752 torr. The mercury level in the open arm is 26 mm above that in the arm connected to the flask of helium. What is the helium pressure, in torr?

Accepted Answer

A)  -26 torr 
B)  26 torr 
C)  726 torr 
D)  778 torr 
E)  None of these choices is correct. 
A)  -26 torr 
B)  26 torr 
C)  726 torr 
D)  778 torr 
E)  None of these choices is correct.

Question 13

"The pressure of an ideal gas is inversely proportional to its volume at constant temperature and number of moles" is a statement of __________________ Law.

Accepted Answer

A)  Charles's 
B)  Boyle's 
C)  Amontons's 
D)  Avogadro's 
E)  Gay-Lussac's 
A)  Charles's 
B)  Boyle's 
C)  Amontons's 
D)  Avogadro's 
E)  Gay-Lussac's

Question 14

If 0.750 L of argon at 1.50 atm and 177$\degree$C and 0.235 L of sulfur dioxide at 95.0 kPa and 63.0$\degree$C are added to a 1.00-L flask and the flask's temperature is adjusted to 25.0$\degree$C, what is the resulting pressure in the flask?

Accepted Answer

A)  0.0851 atm 
B)  0.244 atm 
C)  0.946 atm 
D)  1.74 atm 
E)  1.86 atm 
A)  0.0851 atm 
B)  0.244 atm 
C)  0.946 atm 
D)  1.74 atm 
E)  1.86 atm

Question 15

The most probable speed of an oxygen molecule in the gas phase at room temperature is 450 m/s. The root-mean-square speed (urms) is therefore

Accepted Answer

A)  equal to 450 m/s. 
B)  slightly less than 450 m/s. 
C)  much less than 450 m/s. 
D)  slightly greater than 450 m/s. 
E)  much greater than 450 m/s. 
A)  equal to 450 m/s. 
B)  slightly less than 450 m/s. 
C)  much less than 450 m/s. 
D)  slightly greater than 450 m/s. 
E)  much greater than 450 m/s.

Question 16

Starting from the Ideal Gas Equation, derive an equation corresponding to Charles's Law, stating all important assumptions or conditions.

Accepted Answer

Ideal Gas Equation is PV = nRT. Charles'

Question 17

Which of the lines on the figure below is the best representation of the relationship between the volume and the number of moles of a gas, measured at constant temperature and pressure?

Accepted Answer

A)  a 
B)  b 
C)  c 
D)  d 
E)  e 
A)  a 
B)  b 
C)  c 
D)  d 
E)  e

Question 18

Mineral oil can be used in place of mercury in manometers when small pressure changes are to be measured. What is the pressure of an oxygen sample in mm of mineral oil if its pressure is 28.5 mm Hg? (d of mineral oil = 0.88 g/mL; d of Hg = 13.5 g/mL)

Accepted Answer

A)  1.9 mm mineral oil 
B)  15 mm mineral oil 
C)  32 mm mineral oil 
D)  380 mm mineral oil 
E)  440 mm mineral oil 
A)  1.9 mm mineral oil 
B)  15 mm mineral oil 
C)  32 mm mineral oil 
D)  380 mm mineral oil 
E)  440 mm mineral oil

Question 19

State Charles's Law and illustrate it with a graph, using standard x-y coordinate axes. Be sure to label the axes unambiguously with the correct gas variables.

Accepted Answer

At constant pressure, the volume of a fi

Question 20

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

Exam 5: Gases and the Kinetic-Molecular Theory

For an ideal gas, a plot of PV/nRT versus P gives a straight line with a positive slope.

"The pressure of an ideal gas is directly proportional to its absolute temperature at constant volume and number of moles" is a statement of ________________ Law.

A sample of nitrogen gas is confined to a 14.0 L container at 375 torr and 37.0 °\degree° C. How many moles of nitrogen are in the container?

A sample of methane gas, CH4(g), occupies a volume of 60.3 L at a pressure of 469 torr and a temperature of 29.3 °\degree° C. What would be its temperature at a pressure of 243 torr and volume of 60.3 L?

A flask containing neon gas is connected to an open-ended mercury manometer. The open end is exposed to the atmosphere, where the prevailing pressure is 745 torr. The mercury level in the open arm is 50. mm below that in the arm connected to the flask of neon. What is the neon pressure, in torr?

At a temperature of absolute zero, the volume of an ideal gas is zero.

Calculate the root-mean-square speed of methane, CH4 (g), at 78 °\degree° C.

An unknown liquid is vaporized in a 273-mL flask by immersion in a water bath at 99 °\degree° C. The barometric pressure is 753 torr. If the mass of the vapor retained in the flask is 1.362 g, what is its molar mass?

Mercury is 13.6 times as dense as liquid water. What would be the reading of a water-filled barometer at normal atmospheric pressure, 760. mmHg?

A 750-mL sample of hydrogen exerts a pressure of 822 torr at 325 K. What pressure does it exert if the temperature is raised to 475 K at constant volume?

"The pressure of an ideal gas is inversely proportional to its volume at constant temperature and number of moles" is a statement of __________________ Law.

If 0.750 L of argon at 1.50 atm and 177 °\degree° C and 0.235 L of sulfur dioxide at 95.0 kPa and 63.0 °\degree° C are added to a 1.00-L flask and the flask's temperature is adjusted to 25.0 °\degree° C, what is the resulting pressure in the flask?

The most probable speed of an oxygen molecule in the gas phase at room temperature is 450 m/s. The root-mean-square speed (urms) is therefore

Starting from the Ideal Gas Equation, derive an equation corresponding to Charles's Law, stating all important assumptions or conditions.

Which of the lines on the figure below is the best representation of the relationship between the volume and the number of moles of a gas, measured at constant temperature and pressure?

Mineral oil can be used in place of mercury in manometers when small pressure changes are to be measured. What is the pressure of an oxygen sample in mm of mineral oil if its pressure is 28.5 mm Hg? (d of mineral oil = 0.88 g/mL; d of Hg = 13.5 g/mL)

State Charles's Law and illustrate it with a graph, using standard x-y coordinate axes. Be sure to label the axes unambiguously with the correct gas variables.

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

Keys to the Study of Chemistry

The Components of Matter

Stoichiometry of Formulas and Equations

Three Major Classes of Chemical Reactions

Thermochemistry: Energy Flow and Chemical Change

Quantum Theory and Atomic Structure

Electron Configuration and Chemical Periodicity

Models of Chemical Bonding

The Shapes of Molecules

Theories of Covalent Bonding

Intermolecular Forces: Liquids, Solids, and Phase Changes

The Properties of Mixtures: Solutions and Colloids

Periodic Patterns in the Main-Group Elements

Organic Compounds and the Atomic Properties of Carbon

Kinetics: Rates and Mechanisms of Chemical Reactions

Equilibrium: the Extent of Chemical Reactions

Acid-Base Equilibria

Ionic Equilibria in Aqueous Systems

Thermodynamics: Entropy, Free Energy, and the Direction of Chemical Reactions

Electrochemistry: Chemical Change and Electrical Work

The Elements in Nature and Industry

The Transition Elements and Their Coordination Compounds

Nuclear Reactions and Their Applications

Filters

A sample of nitrogen gas is confined to a 14.0 L container at 375 torr and 37.0 $\degree$ C. How many moles of nitrogen are in the container?

A sample of methane gas, CH₄(g), occupies a volume of 60.3 L at a pressure of 469 torr and a temperature of 29.3 $\degree$ C. What would be its temperature at a pressure of 243 torr and volume of 60.3 L?

Calculate the root-mean-square speed of methane, CH₄ (g), at 78 $\degree$ C.

An unknown liquid is vaporized in a 273-mL flask by immersion in a water bath at 99 $\degree$ C. The barometric pressure is 753 torr. If the mass of the vapor retained in the flask is 1.362 g, what is its molar mass?

If 0.750 L of argon at 1.50 atm and 177 $\degree$ C and 0.235 L of sulfur dioxide at 95.0 kPa and 63.0 $\degree$ C are added to a 1.00-L flask and the flask's temperature is adjusted to 25.0 $\degree$ C, what is the resulting pressure in the flask?

The most probable speed of an oxygen molecule in the gas phase at room temperature is 450 m/s. The root-mean-square speed (u_rms) is therefore

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