what is the effect of charge and radius size on the acidity of a cation?

Question

what is the effect of charge and radius size on the acidity of a cation? Is it possible to predict the comparative pH of "In 3+" vs. "Al 3+"?

Answer 1

Higher the charge greater the tendency to accept electrons, hence more acidic

Lower the radius, higher concentration of charge, hence more acidic.

In3+ is larger than Al3+ hence a weaker acid.