# Ideal gas equation, Internal Energy, Equipartition of energy

1. A scuba tank has a volume of 3500 cm³. The tank is filled with 50% (by volume) pure oxygen and 50% (by volume) pure helium.

(a) How many molecules are there of each type in tank if it is filled at 20ºC to an absolute pressure of 11 atmospheres?

(b) What is the ratio of the average translational kinetic energies of the two types of molecules?

(c) Use the equipartition of energy principle to principle to predict the ratio of the internal energies of the two gases.

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(a) How many molecules are there of each type in tank if it is filled at 20ºC to an absolute pressure of 11 atmospheres?

Ideal gas Law

PV=nRT

or n=PV/RT

P=Pressure= 11 atm= 1114575 N/m^2 =11*101325

(1 atm= 101325 N/m^2)

V=Volume= 3500/2= 1750 cm^3= 0.00175 m^3

n=no of moles

R= Gas constant= 8.314 J.mol ^-1K ...

#### Solution Summary

Answers questions based on Ideal gas equation, Internal Energy, Equipartition of energy principle, Average translational kinetic energies.