One litre buffer solution was prepared by adding \(0.10\) \(\text{mol}\) each of \(NH_3\) and \(NH_4Cl\) in deionized water. The change in \(\mathrm{pH}\) on addition of \(0.05\) \(\text{mol}\) of \(HCl\) to the above solution is ______ \(\times 10^{-2}\). (Nearest integer)
Given: \(pK_b\) of \(NH_3 = 4.745\) and \(\log_{10} 3 = 0.477\)
