Question

Why is PF3 more acidic among all trihalides?
i want correct vaule points from a real chemistry teacher

Answer 1

The high acidity is because of the following facts;
1) After forming 3 bonds with fluride ion, it has vaccant d orbitals.And it possess a lone pair of electron too.
2)Flourine is highley electronegative.So it try to pull the electron density strongly.
So flourine accepts electron pair and becomes the lewis acid.

This is why PF3 is most acidic halide.