Question

A 2 lt flask contains 1.6 g of methane and 0.5 g of hydrogen at 27°c calculate the partial pressure of each gas in the mixture and hence calculate the total pressure

Answer 1

V=2 l.

m(CH4)= 1.6 g.  

m(H2)= 0.5 g.

T=27° C = 300 K

P(CH4)=?

P(H2)=?

Ptot=?

Formula: PV=(mRT)/M

therefore P=(mRT)/MV

and Ptot= P(CH4)+ P(H2)

P(CH4)=(1.6 x 8.314 x 300)/(16 x 2)=124.71 kpa.

P(H2)=(0.5 x 8.314 x 300)/(2 x 2)=311.775 kpa.

Ptot=124.71+311.775=436.485