Question

What mass, in grams, of oxygen gas (O2) is contained in a 8.5 liter tank at 32.0 degrees Celsius and 3.23 atmospheres? Show all of the work used to solve this problem.

Answer 1

use PV=nRT

you know that n = number of moles; n=m/MW i.e.. mass divided by molecular weight.

rewrite the equation substituting the n variable

PV=(m/MW)RT

use some algebra and isolate m

m=(PxVxMW)/(RT)

don't forget to convert T (celsius to kelvin)
and use the correct R value; R = 0.08206 L·atm/mol·K