Answer. Acidic salt is formed by partial replacement of replaceable H+ ions of an acid by a positive metal ion,
H2SO4(aq) +KOH(aq) KHSO4(aq) + H2O(1)
If molar ratio, of H2SO4 and KOH is 1:1 then acidic salt, is formed. If ratio is 1:2 then neutral salt is formed. It means nature of salt formation depends upon molar ratio of an acid and a base.