HELLO I NEED HELP AND NOBODY EVER HELPS ME.
posted by billystar .
1. the molar mass of helium is 4.00 g/mol.
calculate the volume of 1 mol of helium at STP (T = 273, P = 1 atm)
what is the density of helium at STP?
2. the density of an ideal gas is 1.35 kg/m^3. if the temperature is Kelvin and the pressure are both doubled, find the new density of the gas.

well nobody is gonna help you with that attitude :(

1)
V = nRT/P
= (1 x 8.314 x 273/101.23)
= 22.4 L
so the density is 4g/22.4L
2) assuming the volume is held constant, the density would be the same.