Page 142 - Bruno Linder Elementary Physical Chemistry

August 18, 2010 11:37 9in x 6in b985-appA Elementary Physical Chemistry

Appendix A

Homework Problem Sets

Problem Set I. Chapter 1
1. Calculate the pressure of 0.300g of Ar occupying a volume of 400 dm 3
at 450 K.
◦
2. A gas in a constant volume container has a pressure of 150 kPa at 25 C.
◦
Calculate the pressure at 250 C.
3. A gas in a balloon has a pressure of 100 kPa, a temperature of 25 C
◦
3
and a volume of 10 cm . What will the volume of the balloon be if it
rises to an altitude where the atmospheric pressure is 100 Pa and the
◦
temperature is −50 C?
4. The balloon of Problem 3 is lowered at sea to a depth of 30 m. The
3
density of sea water is 1.025 g/cm and assumed to be constant. The
temperature is also assumed to be constant. The gravitational constant
is g =9.81ms −2 . The atmospheric pressure is 100 kPa. What is the
volume of the air in the balloon at a depth of 30 m?
5. A gas mixture is composed of 300mg of CH 4 and 200mg of N 2 .The
partial pressure of CH 4 is 120 kPa at 300 K. Calculate the partial pressure
of N 2 , the total pressure of the mixture and the volume of the mixture.
6. Calculate the molar mass of 40 mg of a gas, occupying a volume of
3
250cm at a pressure of 175atm and a temperature of 300 K.
7. Calculate the root-mean-square speed, c rms ,ofan Ar atomata pressure
of 1 bar and a temperature of 298 K.
2
8. The cross-section of Ar is σ =0.36nm . Calculate the root-mean-
square speed, c rms, the diameter, d, the mean free path, λ,and
5
collision frequency, z. The pressure of the gas is 1 bar (10 Pa) and
◦
the temperature is 25 C.

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