What is Kb for CN-(aq) H2O(l) HCN(aq) OH-(aq)?

Answer 1

The base dissociation constant ((K_b)) for the cyanide ion ((CN^-)) can be derived from the equilibrium expression for its reaction with water: (CN^- + H_2O \rightleftharpoons HCN + OH^-). The (K_b) value can be calculated using the relationship (K_b = \frac{K_w}{K_a}), where (K_w) is the ion product of water (1.0 x (10^{-14}) at 25°C) and (K_a) is the acid dissociation constant for hydrogen cyanide (HCN). Given that (K_a) for HCN is approximately (6.2 \times 10^{-10}), you can substitute this value into the equation to find (K_b). Thus, (K_b \approx \frac{1.0 \times 10^{-14}}{6.2 \times 10^{-10}} \approx 1.61 \times 10^{-5}).