An aqueous solution of an acid is so weak that it can be assumed to be practically unionised, boiled at `100.4^(circ)C`. `25 mL` of this solution was neutralised by `38.5 mL` of `1N` solution of `NaOH`. Calculate basicity of the acid if `K_(b)` for water is `0.52 K mol^(-1) kg`. Assume molality equal to molarity.