Chemistry Chapter 11 The value of the gas constant R is equal to

Introductory Chemistry: Atoms First, 5e (Russo/Silver)

Chapter 11 What If There Were No Intermolecular Forces? – The Ideal Gas

11.1 Multiple Choice Questions

1) Pressure is defined as ________.

A) the amount of force per unit area

B) the amount of force per unit volume

C) the amount of work per unit area

D) the amount of work per unit volume

2) 1 atm is equal to ________. 1 atm = 760 torr.

A) 760 cm Hg

B) 760 mm Hg

C) 76 torr

D) 76 mm Hg

3) 0.15 atm is equal to ________. 1 atm = 760 torr.

A) 11.4 torr

B) 114 torr

C) 1.14 × 10-5 torr

D) 1.14 × 10-3 torr

4) 380 mm Hg is equal to ________ atm.

A) 0.50

B) 2.0

C) 5.0

D) 20.0

5) 855 torr is equal to ________ cm Hg. 1 atm = 760 torr.

A) 1.13

B) 85.5

C) 855

D) 8550

6) A pressure of 76.0 cm Hg would be equivalent to what height of a water column? The density

of mercury = 13.6 g/mL.

A) 5.59 cm

B) 55.9 cm

C) 0.18 cm

D) 1030 cm

7) The value of the gas constant R is equal to ________ L∙atm/ K∙mole.

A) 0.0821

B) 8.21

C) 82.1

D) 0.00821

8) If the pressure of a gas sample is quadrupled and the absolute temperature is doubled, by what

factor does the volume of the sample change?

A) 2

B) 1/2

C) 1/4

D) 1/8

9) A gas under an initial pressure of 0.60 atm is compressed at constant temperature from 27 L to

3.0 L. The final pressure becomes ________.

A) 0.060 atm

B) 0.54 atm

C) 5.4 atm

D) 54 atm

10) How many moles of gas are found in a container that occupies a volume of 5.50 L with a

pressure of 0.335 atm at

A) 0.0753 moles

B) 0.898 moles

C) 13.3 moles

D) 1.11 moles

11) The number of moles of hydrogen gas present in a 1,500 mL container at 298 K and 2.0 atm

pressure is ________.

A) 0.65 moles

B) 0.12 moles

C) 0.26 moles

D) 0.52 moles

12) For an ideal gas, which pairs of the variables below are inversely proportional to each

assuming all other variables are kept constant?

A) P and n

B) V and T

C) V and P

D) V and n

13) For an ideal gas, which pairs of the variables below are directly proportional to each

assuming all other variables are kept constant?

A) P and n

B) n and T

C) V and P

D) all of the above

14) A fixed amount of a gas has both its temperature and volume doubled. What happens to its

pressure?

A) It doubles.

B) It is halved.

C) It quadruples.

D) It remains the same.

15) Imagine a balloon that you blow up to a full size. What do you expect to happen if you pour

liquid nitrogen at 77 K over the surface of the balloon? Assume that the pressure does not change

significantly.

A) increase slightly in size

B) decrease significantly in size

C) stay exactly the same size as before

D) One cannot say unless the composition of the gas is known.

16) Imagine a balloon that you blow up to a full size. What do you expect to happen if you

suspend the balloon over a bunsen burner? Assume that the pressure does not change

significantly.

A) increase significantly in size until it bursts

B) decrease significantly in size

C) stay exactly the same size as before

D) One cannot say unless the composition of the gas is known.

17) Calculate the volume occupied by 18.0 g of water vapor at 100 °C and 1.00 atm.

A) 11.2 L

B) 22.4 L

C) 30.6 L

D) 61.2 L

18) Assuming that the pressure and quantity of a gas sample remain constant, what will be the

final volume of a 4.86 L sample of a gas at 281 °C which is cooled to 225 °C?

A) 5.19 L

B) 4.37 L

C) 2.92 L

D) 2.78 L

19) Assuming that the pressure and quantity of a gas sample remain constant, what will be the

final volume of a 4.86 L sample of a gas at 281 °C when it is heated to 300 °C?

A) 5.03 L

B) 3.89 L

C) 2.92 L

D) 2.78 L

20) 1.86 moles of a gas occupy 245 L at 281 °C under a pressure of 0.346 atm. When the

pressure is increased to 0.886 atm while keeping the same temperature, the new volume will be

________.

A) 627 L

B) 799 L

C) 95.7 L

D) 47.8 L

21) Assume that the temperature and quantity of a gas sample remain constant. A 1.6 L sample

of a gas is originally at 330 K and 4.84 atm. Calculate the final pressure when the volume is

reduced to 840 mL.

A) 9.22 atm

B) 4.61 atm

C) 18.44 atm

D) 3.66 atm

22) A 4.23 L sample of a gas is originally at 747 mm Hg at 297 K. The volume occupied by the

same quantity of gas under the same temperature and 700. torr is ________. 1 atm = 760 torr.

A) 3.96 L

B) 4.51 L

C) 1.88 L

D) 1.68 L

23) A gas occupies 340 mL at 273 K and 610 torr. What is the final temperature when the

pressure is increased to 1 atm, and the volume being held constant? 1 atm = 760 torr.

A) 67 °C

B) 267 °C

C) 340 °C

D) 613 °C

24) Which statement is true for an ideal gas?

A) The pressure of a gas increases when its volume decreases.

B) The pressure of a gas increases when its temperature increases.

C) The pressure of a gas increases when the number of gas moles increases.

D) All of the above statements are correct.

25) A gas sample occupies a volume of 8 L at 20 °C. What is the temperature at which the gas

would double its volume?

A) 40 °C

B) 10 °C

C) 273 K

D) 586 K

26) 0.024 moles of nitrogen gas occupy 4.0 L at 0.90 atm pressure. What will be the final volume

if the container is allowed to expand and the pressure is reduced to 0.30 atm while the

temperature is kept constant?

A) 1.33 L

B) 3.6 L

C) 6.0 L

D) 12 L

27) If the volume of a given gas sample doubles, what happens to the temperature of the gas?

The amount of gas and the pressure of the gas stay the same.

A) increase by a factor of 2

B) decrease by a factor of 2

C) stay exactly the same

28) If the pressure of a given gas sample doubles, what happens to the volume of gas? The

amount of gas and the temperature of the gas stay the same.

A) increase by a factor of 2

B) decrease by a factor of 2

C) stay exactly the same

29) A gas occupies a volume of 480 mL at 127 °C and 140 mm Hg. What mathematical

expression will yield the correct volume at 177 °C and 400 mm Hg?

A) 480 × (140/400) × (450/400)

B) 480 × (400/140) × (450/400)

C) 480 × (140/400) × (400/450)

D) 480 × (400/140) × (400/450)

30) A gas occupies a volume of 0.500 L at 125 °C and 0.443 atm. What mathematical expression

will yield the correct temperature at 0.750 L and 0.689 atm?

A) (0.689 × 0.750 × 125)/(0.443 × 0.500)

B) (0.443 × 0.500 × 398)/(0.689 × 0.750)

C) (0.443 × 0.500)/(0.689 × 0.750 × 398)

D) (0.689 × 0.750 × 398)/(0.443 × 0.500)

31) STP conditions stand for ________.

A) 0 K, 1 atm

B) 0 °C, 760 cm Hg

C) 0 °C, 760 mm Hg

D) 0 K, 76 cm Hg

32) A gas occupies 2.00 L at 298 K and 2.10 atm. The volume of this gas at STP is ________.

A) 22.4 L

B) 2.24 L

C) 3.84 L

D) 2.00 L

33) Which of the following gases occupy the largest volume at STP?

A) 12.00 g He

B) 2 mol of water

C) 38.00 g F2

D) 6.022 × 1023 molecules of ammonia

34) The volume of 2.3 g nitrogen gas at STP is ________.

A) 1.8 L

B) 11.2 L

C) 22.4 L

D) 44.8 L

35) Which of the following gases will have the same density at STP?

A) oxygen and methane

B) hydrogen and helium

C) carbon monoxide and nitrogen

D) hydrogen chloride and fluorine

36) Which of the following gases occupy the smallest volume at STP?

A) 4.032 g H2

B) 1.000 mol of carbon dioxide

C) 35.45 g Cl2

D) 6.022 × 1023 molecules of O2

37) The density of carbon dioxide as STP is ________.

A) 0.46 g/ L

B) 1.97 g/ L

C) 3.94 g/ L

D) 5.62 g/ L

38) What weight of nitrogen gas will occupy a volume of 1.25 L at a pressure of 1.0 atm and a

temperature of 200.°C?

A) 0.45 g

B) 0.90 g

C) 1.80 g

D) 3.60 g

39) The volume occupied by 4.00 g oxygen gas at STP is ________.

A) 22.4 L

B) 11.2 L

C) 5.60 L

D) 2.80 L

40) 0.249 g of a diatomic element occupies a volume of 125. mL at 120. °C and 2.00 atm. This

element is ________.

A) nitrogen

B) oxygen

C) chlorine

D) bromine

41) An unknown gaseous substance has a density of 1.06 g/L at 31 °C and 371 torr. Its molecular

weight is ________.

A) 27 g/mol

B) 54 g/mol

C) 81 g/mol

D) 108 g/mol

42) An unknown gaseous substance has a density of 1.06 g/L at 31 °C and 371 torr. If the

substance has the following percent composition: 88.8% C and 11.2% H, its molecular formula

is ________.

A) CH3

B) C2H3

C) C4H6

D) C2H5

43) The density of hydrogen gas at STP is ________ the density of oxygen under identical

conditions.

A) four times larger than

B) eight times larger than

C) sixteen times smaller than

D) equal to, since both densities are taken under the same conditions

44) 0.123 g of a gas occupy a volume of 124 mL at 120. °C and 760. torr. Its molar mass is

________ g/mol.

A) 22.4

B) 28.1

C) 71.1

D) 32.0

45) 0.123 g of a gas occupy a volume of 124 mL at 120. °C and 760. torr. The possible formula

of the gas is ________.

A) CH4

B) CO2

C) Cl2

D) O2

46) The molar volume of an ideal gas is ________.

A) always equal to 22.4 L at room temperature

B) proportional to the molecular weight of the gas

C) always equal to 22.4 L at STP

D) inversely proportional to the molecular weight of the gas

47) Which gas has a density equal to 1.43 g/L at STP?

A) nitrogen

B) oxygen

C) helium

D) carbon monoxide

48) The density of carbon tetrachloride at 0.94 atm and 398 K is ________.

A) 1.11 g/L

B) 2.21 g/L

C) 4.43 g/L

D) 8.86 g/L

49) The density of sulfur vapor at 1273 K and 740 mm Hg is 0.5977 g/L. Its molar mass is

________.

A) 32

B) 64

C) 96

D) 128

50) The density of sulfur vapor at 1273 K and 740 mm Hg is 0.5977 g/L. Sulfur at that

temperature will be ________.

A) monoatomic

B) diatomic

C) triatomic

D) tetraatomic