A gaseous compound has a density of 1.56 g/L at 27.0 °C and 1.33 atm. What is the molar mass of the compound?

Question

A gaseous compound has a density of 1.56 g/L at 27.0 °C and 1.33 atm. What is the molar mass of the compound?

Answer 1

PV=nRT

 

D=m/V

Molar Mass=m/n

so

m=DV

m=nMM

so

DV=nMM

so

V=nMM/D

 

Plug into PV=nRT

 

PnMM/D=nRT

n on both sides cancel

 

PMM/D=RT

 

Solve for MM

 

MM=DRT/P

 

Plug in

D=1.56g/L

T=27+273=300K

R=0.0821 L*atm/K*mol

P=1.33atm