Question

Predict the direction in which the equilibrium will lie for the reactionC6H5COO- + HF C6H5COOH + F-.Ka(C6H5COOH) = 6.5 x 10-5; Ka(HF) = 7.1 x 10-4In the middleTo the rightTo the left

Answer 1

Equilibrium will lie to the right.

Step-by-step explanation:

`K_(a)(HF)> K_(a)(C_(6)H_(5)COOH)`

That means HF is stronger acid than
`C_(6)H_(5)COOH`.

Alternatively, it can be said that
`C_(6)H_(5)COO^(-)` is a stronger base than
`F^(-)`.

Therefore HF readily gives proton to
`C_(6)H_(5)COO^(-)` to form
`C_(6)H_(5)COOH` and
`F^(-)` than the reverse reaction.

So, the equilibrium will lie more towards the right i.e. towards formation of
`C_(6)H_(5)COOH` and
`F^(-)`.