`BF_3` acts as a Lewis acid. Why ?

Account for the following: NH_3 acts as a Lewis base.

Though fluorine is more electronegative than chlorine yet BF_3 is a weaker lewis acid than BCl_3 , why ?

SOCl_2 can act as a weak Lewis acid as well as a weak Lewis base. Explain.

Explain the nature of boric acid as a Lewis acid in water.

Why does ammonia act as a Lewis base ?

Dry chlorine does not act as a bleaching agent. Why?

Which is a stronger Lewis acid and why ? BF_3 OR BCl_3

Classify the followings into Lewis acids and Lewis bases and show how these act as Lewis acid/base ? BCl_(3)

Classify the followings into Lewis acids and Lewis bases and show how these act as Lewis acid/base ? OH^(-)