Question 1

STP stands for ________ _______ ________ ________.

Accepted Answer

standard t...

Question 2

A gaseous compound is 30.4% nitrogen and 69.6% oxygen by mass. A 5.25-g sample of the gas occupies a volume of 1.00 L and exerts a pressure of 1.26 atm at -4.0°C. What is its molecular formula? (R = 0.08206 L • atm/K • mol)

Accepted Answer

A)   NO
B)   NO2
C)   N3O6
D)   N2O4
E)   N2O5F) B) and C)
G) C) and D)

Question 3

According to the postulates of kinetic molecular theory, the molecules of all gases at a given temperature have the same average speed.

Accepted Answer

A) True 
 B)False

Question 4

What is the final temperature of a gas that expands from a volume of 22.4 L at 278 K to a volume of 38.3 L at constant pressure?

Accepted Answer

A)   163 K
B)   294 K
C)   3.09 K
D)   217 K
E)   475 KF) A) and E)
G) A) and D)

Question 5

Magnesium metal (0.100 mol)  and hydrochloric acid (0.500 mol HCl)  are combined and react to completion. What volume of hydrogen gas, measured at STP, is produced? Mg(s)  + 2HCl(aq)  → MgCl2(aq)  + H2(g) 
(R = 0.08206 L • atm/K • mol)

Accepted Answer

A)   2.24 L of H2
B)   4.48 L of H2
C)   5.60 L of H2
D)   11.2 L of H2
E)   22.4 L of H2F) A) and D)
G) A) and E)

Question 6

Suppose a sample of gas is composed of 100 molecules, with speeds given below.  According to the kinetic molecular theory, if the absolute temperature of the gas is halved, what is a reasonable estimation of the new distribution of speeds of the molecules?

Accepted Answer

A)   
B)   
C)   
D)   
E)   F) A) and B)
G) B) and D)

Question 7

Choose all answers that apply. Which of the following is/are characteristic(s)  of gases?

Accepted Answer

A)   High compressibility
B)   Has a static volume regardless of temperature and pressure
C)   Formation of homogeneous mixtures regardless of the nature of gases
D)   Relatively large distances between molecules
E)   Always has a density of 1.00 gram per literF) B) and C)
G) A) and E)

Question 8

A block of dry ice (solid CO2, density = 1.56 g/mL)  of dimensions 25.0 cm × 25.0 cm × 25.0 cm is left to sublime (i.e., to pass from the solid phase to the gas phase)  in a closed chamber of dimensions 4.00 m × 5.00 m × 3.00 m. Once the sublimation is complete, what is the partial pressure of carbon dioxide in the chamber at 25°C? (R = 0.08206 L • atm/K • mol, 1 atm = 760 mmHg)

Accepted Answer

A)   172 mmHg
B)   107 mmHg
C)   0.225 mmHg
D)   0.172 mmHg
E)   14.4 mmHgF) D) and E)
G) C) and D)

Question 9

Select the gas with the highest average kinetic energy per mole at 298 K.

Accepted Answer

A)   O2
B)   CO2
C)   H2O
D)   H2
E)   All have the same average kinetic energy.F) None of the above
G) A) and D)

Question 10

What is the mass, in grams, of 2.74 L of CO gas measured at 33°C and 945 mmHg? (R = 0.08206 L • atm/mol • K, 1 atm = 760 mmHg)

Accepted Answer

A)   0.263 g
B)   2.46 g
C)   3.80 g
D)   35.2 g
E)   206 gF) B) and D)
G) B) and C)

Question 11

What is the Kelvin temperature at 24°C?

Accepted Answer

A)   249 K
B)   11.4 K
C)   -297 K
D)   -249 K
E)   297 KF) A) and E)
G) A) and C)

Question 12

If equal masses of O2(g)  and HBr(g)  are in separate containers of equal volume and temperature, which one of the following statements is true?

Accepted Answer

A)   The pressure in the O2 container is greater than that in the HBr container.
B)   The average velocity of the O2 molecules is less than that of the HBr molecules.
C)   The average kinetic energy of HBr molecules is greater than that of O2 molecules.
D)   The pressures of both gases are the same.E) A) and B)
F) B) and C)

Question 13

Packaged cake mixes usually contain baking powder, a mixture of sodium hydrogen carbonate and calcium hydrogen phosphate that react to produce carbon dioxide gas when they come into contact with water. Many such mixes have special instructions for use at high altitudes. Why?

Accepted Answer

The baking powder acts as a le...

Question 14

The pressure of hydrogen sulfide gas in a container is 3.565 ×104 Pa. What is this pressure in torr? (1 atm = 101,325 Pa = 760 torr) ?

Accepted Answer

A)   46.91 torr
B)   267.4 torr
C)   351.8 torr
D)   3612 torr
E)   2.709 ×104 torrF) D) and E)
G) A) and D)

Question 15

Which of the following gases effuses most rapidly?

Accepted Answer

A)   nitrogen
B)   oxygen
C)   hydrogen chloride
D)   ammonia
E)   carbon monoxideF) B) and D)
G) B) and C)

Question 16

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. Mg(s)  + 2HCl(aq)  → MgCl2(aq)  + H2(g) 
(R = 0.08206 L • atm/K • mol)

Accepted Answer

A)   3.4 × 10-3 L
B)   2.2 L
C)   2.9 L
D)   5.8 L
E)   11.7 LF) B) and C)
G) A) and C)

Question 17

Arrange the following gases in order of increasing rate of effusion: C2H6, Ar, HCl, and 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 < C2H6F) D) and E)
G) C) and D)

Exam 10: Gases

A gaseous compound is 30.4% nitrogen and 69.6% oxygen by mass. A 5.25-g sample of the gas occupies a volume of 1.00 L and exerts a pressure of 1.26 atm at -4.0°C. What is its molecular formula? (R = 0.08206 L • atm/K • mol)

Correct Answer
verified

Select the gas with the highest average kinetic energy per mole at 298 K.

Correct Answer
verified

According to the postulates of kinetic molecular theory, the molecules of all gases at a given temperature have the same average speed.

Correct Answer
verified

What is the mass, in grams, of 2.74 L of CO gas measured at 33°C and 945 mmHg? (R = 0.08206 L • atm/mol • K, 1 atm = 760 mmHg)

Correct Answer
verified

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

Correct Answer
verified

What is the final temperature of a gas that expands from a volume of 22.4 L at 278 K to a volume of 38.3 L at constant pressure?

Correct Answer
verified

Suppose a sample of gas is composed of 100 molecules, with speeds given below. According to the kinetic molecular theory, if the absolute temperature of the gas is halved, what is a reasonable estimation of the new distribution of speeds of the molecules?

Correct Answer
verified

Magnesium metal (0.100 mol) and hydrochloric acid (0.500 mol HCl) are combined and react to completion. What volume of hydrogen gas, measured at STP, is produced? Mg(s) + 2HCl(aq) → MgCl₂(aq) + H₂(g) (R = 0.08206 L • atm/K • mol)

Correct Answer
verified

Correct Answer
verified

The pressure of hydrogen sulfide gas in a container is 3.565 ×10⁴ Pa. What is this pressure in torr? (1 atm = 101,325 Pa = 760 torr) ?

Correct Answer
verified

Which of the following gases effuses most rapidly?

Correct Answer
verified

Packaged cake mixes usually contain baking powder, a mixture of sodium hydrogen carbonate and calcium hydrogen phosphate that react to produce carbon dioxide gas when they come into contact with water. Many such mixes have special instructions for use at high altitudes. Why?

Correct Answer
verified
The baking powder acts as a le...
View Answer

STP stands for ____ _ __.

Correct Answer
verified
standard t...
View Answer

If equal masses of O₂(g) and HBr(g) are in separate containers of equal volume and temperature, which one of the following statements is true?

Correct Answer
verified

Correct Answer
verified

What is the Kelvin temperature at 24°C?

Correct Answer
verified

Choose all answers that apply. Which of the following is/are characteristic(s) of gases?

Correct Answer
verified

Exam 10: Gases

A gaseous compound is 30.4% nitrogen and 69.6% oxygen by mass. A 5.25-g sample of the gas occupies a volume of 1.00 L and exerts a pressure of 1.26 atm at -4.0°C. What is its molecular formula? (R = 0.08206 L • atm/K • mol)

Correct AnswerverifiedShow Answer

Select the gas with the highest average kinetic energy per mole at 298 K.

Correct AnswerverifiedShow Answer

According to the postulates of kinetic molecular theory, the molecules of all gases at a given temperature have the same average speed.

Correct AnswerverifiedShow Answer

What is the mass, in grams, of 2.74 L of CO gas measured at 33°C and 945 mmHg? (R = 0.08206 L • atm/mol • K, 1 atm = 760 mmHg)

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

What is the final temperature of a gas that expands from a volume of 22.4 L at 278 K to a volume of 38.3 L at constant pressure?

Correct AnswerverifiedShow Answer

Suppose a sample of gas is composed of 100 molecules, with speeds given below. According to the kinetic molecular theory, if the absolute temperature of the gas is halved, what is a reasonable estimation of the new distribution of speeds of the molecules?

Correct AnswerverifiedShow Answer

Magnesium metal (0.100 mol) and hydrochloric acid (0.500 mol HCl) are combined and react to completion. What volume of hydrogen gas, measured at STP, is produced? Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g) (R = 0.08206 L • atm/K • mol)

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

The pressure of hydrogen sulfide gas in a container is 3.565 ×104 Pa. What is this pressure in torr? (1 atm = 101,325 Pa = 760 torr) ?

Correct AnswerverifiedShow Answer

Which of the following gases effuses most rapidly?

Correct AnswerverifiedShow Answer

Packaged cake mixes usually contain baking powder, a mixture of sodium hydrogen carbonate and calcium hydrogen phosphate that react to produce carbon dioxide gas when they come into contact with water. Many such mixes have special instructions for use at high altitudes. Why?

Correct AnswerverifiedThe baking powder acts as a le...View AnswerShow Answer

STP stands for ________ _______ ________ ________.

Correct Answerverifiedstandard t...View AnswerShow Answer

If equal masses of O2(g) and HBr(g) are in separate containers of equal volume and temperature, which one of the following statements is true?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

What is the Kelvin temperature at 24°C?

Correct AnswerverifiedShow Answer

Choose all answers that apply. Which of the following is/are characteristic(s) of gases?

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

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

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Magnesium metal (0.100 mol) and hydrochloric acid (0.500 mol HCl) are combined and react to completion. What volume of hydrogen gas, measured at STP, is produced? Mg(s) + 2HCl(aq) → MgCl₂(aq) + H₂(g) (R = 0.08206 L • atm/K • mol)

Correct Answer
verified

Correct Answer
verified

The pressure of hydrogen sulfide gas in a container is 3.565 ×10⁴ Pa. What is this pressure in torr? (1 atm = 101,325 Pa = 760 torr) ?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
The baking powder acts as a le...
View Answer

STP stands for ____ _ __.

Correct Answer
verified
standard t...
View Answer

If equal masses of O₂(g) and HBr(g) are in separate containers of equal volume and temperature, which one of the following statements is true?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
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