Question

In the reaction `AB(g) hArr A(g) + B(g)` at `30^(@)C, k_(p)` for the dissociation equilibrium is `2.56xx10^(-2) atm`. If the total pressure at equilibrium is 1 atm, then the percentage dissociation of AB is
A. 0.87
B. 0.13
C. 0.435
D. 0.16

Answer 1

Correct Answer - D
`{:(AB(g),hArr,A(g),+,B(g)),(1"mol",,,,),(1-alpha,,alpha,,alpha):}`
Total moles `=1+alpha`
If p is the toal pressure
`p_(A+B)=(1-alpha)/(1+alpha)p,p_(A)=(alpha)/(1+alpha)p,p_(B)=(alpha)/(1+alpha)p`
`:. k_(p)=(alpha^(2)p)/(1-alpha^(2))=(alpha^(2))/(1-alpha) ( :. p=1 atm ~~ alpha^(2))`
`alpha =sqrt(K)=sqrt(2.56 xx 10^(-2))=0.16 i.e., 16%`