What is the for group in glycine? — Ionic Equilibrium Chemistry Question

💡 Solution & Explanation

The acid dissociation constant $K_a$ provided ($1.6 \times 10^{-10}$) corresponds to the loss of a proton from the $-\text{N}^\oplus\text{H}_3$ group to form the neutral $-\text{NH}_2$ group. Therefore, the $-\text{NH}_2$ group acts as the conjugate base. Its $K_b$ can be found using the relation $K_a \times K_b = K_w$. $K_b = \frac{10^{-14}}{1.6 \times 10^{-10}} = 6.25 \times 10^{-5}$. Therefore, correct answer is C.