At equilibrium `X+Y hArr 3Z, 1` mol of `X, 2` mol of Y and `4` mol of Z are contained in a `3-L` vessel. Among the given values of reaction coefficient Q, given at three different instants, which value refers to system at equilibrium?

Answer

C

Explanation

Volume `=3 L`
`{:(,X,+,Y,hArr,3Z),("At eq.",1/3,,2/3,,4/3):}`
`K=([Z]^(2))/([X][Y])=((4/3)^(3))/([2/3][1/3])=10.67`
a. `Q=10, :. Q lt K`
The reaction proceed forward direction to attain the equilibrium value of K
b. `Q=15, :. Q lt K`
The reaction proceeds backward direction to attain the equilibrium value of K `(10.67)`.
c. `Q=10.67, :. Q=K`
The system is at equilibrium