If you filled three balloons with eaqual volumes of hydrogen, argon, and carbon dioxide gas all at the same temperature and pressure, which ballon would weigh the most? The least?
PV = nRT.
If P is constant, R is constant, T is constant, V is constant, then n must constant.
n = grams/molar mass and rearrange to grams = n*molar mass
So the largest grams would be the one with the largest molar mass?
The least in grams would be the one with the smallest molar mass?...