Each of three identical 15.0-L gas cylinders contains 7.50 mol of gas at 295 K. Cylinder A contains He, cylinder B contains O2, and cylinder C contains SO2. According to the kinetic molecular theory, which gas has the highest average speed?

Helium will have the highest average speed

Explanation:

the kinetic molecular theory tells us that the temperature of a gas is directly proportional to the average kinetic energy of the gas. So since all three gases have the same temperature, they must have the same kinetic energy. Kinetic energy is KE = 0.5mv². How then can a gas with such a small molar mass like helium have the same kinetic energy as much heavier gases like oxygen and sulphur dioxide? By having a much larger average speed