Question

at standard temperature and pressure, a 0.50 mol sample of h₂ gas and a separate 1.0 mol sample of o gas have the same
a average molecular kinetic energy
b average molecular speed
c volume
d density

Explanation:

The average molecular kinetic energy of a gas depends only on temperature. At standard temperature and pressure (STP), temperature is constant. So, different gases have the same average molecular kinetic energy. Average molecular speed depends on molar - mass (heavier molecules are slower at the same temperature). Volume is proportional to the number of moles at STP (different number of moles here means different volumes). Density is mass per volume and is different for different gases at STP.

Answer:

A. average molecular kinetic energy