This is a table given in a text book regarding hard acids
How come BF3 is a harder acid than BBr3?
My reasoning: To check which is harder:
1.Both difficult to polarize 2.Both similar in size
It comes down to which has higher positive charge on the B atom. Since there is effective back bonding in BF3, I feel that BBr3 should have higher charge on B, so it should be harder.
Why is the actual answer reversed? Am I on the right track comparing charges on B?
Thanks in advance!