Practice Th.1 Solutions
Temperature and Ideal Gas Laws
Level 1
1.
One mole of an ideal gas has a temperature of 100°C. If this gas fills the 10.0m3 volume of a closed
container, what is the pressure of the gas?
(A) 0.821 Pa (B) 3.06 Pa (C) 83.1 Pa (D) 310 Pa (E) 1.84 × 10 24 Pa
pV = nRT
2.
Which would be the most comfortable temperature for your bath water?
(A) 0ºC (B) 40 K (C) 110ºC (D) 310 K (E) 560 K
Comfortable bath water should be slightly above room temperature. Room temperature is about
20ºC, or 293 K
3. What temperature change on the Kelvin scale is equivalent to a 10 degree change on the Celsius
scale?
(A) 283 K (B) 273 K (C) 18 K (D) 10 K (E) 0
While temperatures are different on the Celsius and Kelvin scale, the temperature intervals are
identical. 1ºC = 274 K, but 1 Cº = 1 K
Level 2
4.
An ideal gas in a closed container initially has volume V, pressure P. and Kelvin temperature T. If the
temperature is changed to 3T, which of the following pairs of pressure and volume values is
possible?
(A) 3P and V (B) P and V (C) P and V/3 (D) P/3 and V (E) 3P and 3V
PV ∝ T so to triple the temperature, the product of P and V must be tripled
5. Two containers are filled with gases at the same temperature. In the container on the left is a gas of
molar mass 2M, volume 2V, and number of moles 2n. In the container on the right is a gas of molar
mass M, volume V, and moles n. Which is most nearly the ratio of the pressure of the gas on the left
to the pressure of the gas on the right?
(A) 1:1 (B) 8:1 (C) 2:1 (D) 16:1 (E) 4:1
P ∝ n/V at constant temperature
Jedi
6.
The absolute temperature of a sample of monatomic ideal gas is doubled at constant volume. What
effect, if any, does this have on the pressure and density of the sample of gas?
Pressure, Density
(A) Remains the same, Remains the same
(B) Remains the same, Doubles
(C) Doubles, Remains the same
(D) Doubles, Is multiplied by a factor of 4
(E) Is multiplied by a factor of 4 Doubles
P ∝ T at constant volume. If T × 2, then P × 2. Since the mass and volume are unchanged, the
density is unchanged as well