Q.

37.8 g of N2O5 was taken in a 1 L reaction vessel and allowed to undergo the following reaction at 500 K

2N2O5(g)2N2O4(g)+O2(g)

The total pressure at equilibrium was found to be 18.65 bar. 

Then, Kp =  ______×10-2 [nearest integer]

Assume N2O5 to behave ideally under these conditions.

Given: R = 0.082 bar L mol-1 K-1                                          [2025]


Ans.

(962)

Initial moles of N2O5(nN2O5)=Given mass of N2O5Molar mass of N2O5=37.8108mol=0.35mol

Initial pressure of N2O5=nN2O5RTV 

=0.35×0.082×5001bar=14.35bar

2N2O5(g)2N2O4(g)+O2(g)t=014.35 bar00  t=14.35-2p2pp  total=14.35+p

Total pressure at equilibrium = 14.35 + p = 18.65, p = 4.3 bar

Kp=PO2×PN2O42PN2O52 =p×(2p)2(14.35-2p)2

=4.3×(2×4.3)2(14.35-2×4.3)2=4.3×(2×4.3)2(5.75)29.62=962×10-2