One mole of N_(2) and 3 mole of PCI_(5) are placed in a 100 litre vessel heated to 227^(@)c. The equilibrium pressure is 2.05 atm. Assuming ideal behaviour, If K_(p)of the reaction PCl_(5) hArr PCl_(3)+Cl_(2) is y xx 10^(-1) then what is 'y'?

One mole of N_(2) and 3 mole of PCI_(5) are placed in a 100 litre vess

1.	One mole of N_(2) and 3 mole of PCI_(5) are placed in a 100 litre vessel heated to 227^(@)c. The equilibrium pressure is 2.05 atm. Assuming ideal behaviour, If K_(p)of the reaction PCl_(5) hArr PCl_(3)+Cl_(2) is y xx 10^(-1) then what is 'y'?
Answer» Solution : TOTAL no. of moles at equilibrium = 4+X Given, total pressure at equilibrium = 2.05 Now PV=nRT (at equilibrium) `2.05 xx 100=(4+x)0.0821 xx 500`, x = 0.9939 Now degree of dissociation of `PCl_(5)=("Mole dissociation")/("Total mole")=(0.9939)/(3)=0.3313` `:. K_(P)=[(""^(n)PCl_(3) xx ""^(n)Cl_(2))/(""^(n)PCl_(5))] xx [(P)/(sum n)]^(+1)` `=(x^(2))/((3-x)) xx ((2.05)/(4+x))` `=0.2 = 2 xx 10^(-1)=y xx 10^(-1) implies y=2`