Sodium nitrite is a salt of strong base and weak acid. Its degree of hydrolysis, h is given by the relation.
pH = \(\frac{1}{2}\) [pKw + pKa + logC]
= \(\frac{1}{2}\) [14 - log(4.5 x 10-4) + log(0.04)]
= \(\frac{1}{2}\) [14 + 3.3468 - 1.398] = 7.97
h = \(\sqrt{\frac{K_w}{K_a\times C}}\) = \(\sqrt{\frac{1\times 10^{-14}}{4.5\times 10^{-4}\times 0.04}}\)
= \(\sqrt{5.56\times 10^{-10}}\) = 2.36 x 10-5
