Question

m-aminophenol is a stronger acid than of o- amino phenol

Answer 1

The Hygrogen present in the amino group of O-aminophenol forms hydrogen bond with phenol (intramolecular H-bonding).hence it does not lose Hydrogen easily. Whereas in M-aminophenol no such bonding take place and hence it is more acidic.

Answer 2

The acidic nature of phenol is due to extra stability of phenoxide ion that is formed after the loss of $H^+ \ ion$ from the -OH group.

If there is any electron donating group bonded at ortho or para position that decreases the acidic nature of phenol. This is because -OH group is "ortho and para" directing.

Hence, its o-amino phenol is less acidic whereas m-amino phenol does not feel electron donating nature of $-NH_2$ at meta position that makes it more acidic than o-aminophenol.