Quiz 5

Which one of the following is a valid statement of Ideal gas law? V/T = PnR V = P/nRT P/T = nRV PT = nRV PV = nRT

PV = nRT

In a gas mixture of He, Ne, and Ar with a total pressure of 8.40 atm, the mole fraction of Ar is ________ if the partial pressures of He and Ne are 1.50 and 2.00 atm, respectively. [Hint: Find PAr, the partial pressure of Ar, using Dalton's law; Then, Mole fraction XAr= PAr/PT] 0.179 0.238 0.417 0.357 0.583

0.583

A sample of a gas (5.0 mol) at 1.0 atm is expanded at constant temperature from 10 L to 15 L. The final pressure is ________ atm. 1.5 7.5 15 3.3 0.67

0.67

A sample of a gas originally at 29 °C and 1.25 atm pressure in a 3.0 L container is allowed to contract until the volume is 2.2 L and the temperature is 11 °C. The final pressure of the gas is ________ atm. 2.1 2.9 1.6 0.38 2.8

1.6

The density of NO2 at 760.0 torr and 25.0 °C is ________ g/L. 9.30 1.88 1.64 1.68 3.27

1.88

A balloon originally had a volume of 4.39 L at 44 °C and a pressure of 729 torr. The balloon must be cooled to ________ °C to reduce its volume to 3.99 L (at constant pressure). 15.1 0.00 546 288 -288

15.1

The molar volume of a gas at STP is ________ L. 1.00 14.7 0.08206 22.4 62.36

22.4

The total pressure in a 12.2 L vessel that contains a mixture of 2.34 g of carbon dioxide, 1.73 g of sulfur dioxide, and 3.33 g of argon, all at 42 °C is ________ mm Hg. [Hint: Find total number of moles present in the mixture first] 0.347 263 116 395 134

263

Standard temperature and pressure (STP), in the context of gases, refers to ________. 298.15 K and 1 torr 273.15 K and 1 pascal 273.15 K and 1 torr 298.15 K and 1 atm 273.15 K and 1 atm

273.15 K and 1 atm

A pressure of 0.500 atm is the same as a pressure of ________ of mm Hg. 29.9 33.0 760. 193 380.

380.

If 3.21 mol of a gas occupies 56.2 L at 44 °C and 793 torr, 4.73 mol of this gas occupies ________ L under the same conditions. 14.7 478 82.8 30.9 61.7

82.8

The temperature of a sample of CH4 gas (10.34 g) in a 50.0 L vessel at 1.33 atm is ________ °C. -195 984 1260 -1260 195

984

Of the following, ________ is a correct statement of Boyle's law. V/P = constant PV = constant n/P = constant P/V = constant V/T = constant

PV = constant

Which one of the following is a valid statement of Avogadro's law? V/T = constant V = constant × P P/T = constant V = constant × n PV = constant

V = constant × n

Of the following, ________ is a valid statement of Charles' law. PV = constant P/T = constant V = constant × n V = constant × P V/T = constant

V/T = constant