The standard Gibbs energy change at `300K` for the reaction `2AhArrB+C` is 2494. `2J`. At a given time, the composition of the reaction mixture is `[A]=1/2, [B]=2` and `[C]=1/2`. The reaction proceeds in the
`(R=8.314JK//"mol"e=2.718)`

Options

A. Forward direction because `Q gt K_(c)`
B. Reverse direction because `Q gt K_(c)`
C. Forward direction because `Q lt K_(c)`
D. Reverse direction because `Q lt K_(c)`

Answer

B

Explanation

`Delta G^(@) = -2*30" RT "log K_(c)`
` 2494.2 = - 2*303 (8.314) (300) log K_(c)`
or log `K_(c) =-0*4342`
or `K_(c)= "antilog" (bar 1*5658) = 0*3679`
Now , when `[A] =1/2, [B] = 2 and [C] = 1/2`
`Q_(c)= ([B][C])/([A]^(2)) = (2xx1/2)/((1/2)^(2))=4`
As `Q_(c) gt K_(c),` reaction will proceed in the reverse direction.