Question

A 15.0-liter tank is filled with oxygen gas, O₂ for use in a hospital. How many grams of O₂ are inside the tank if the pressure is 2.5 atm at 28 ºC? (Molecular weight of O₂ is 32 g/mole).  

Answer 1

PV$=nRT$

$2.5×15=n×0.08205×(273.15+28)$

$n=1.518$ moles

Mass $=1.518×32$

$=48.56g$