Answer
(a) $$K_c = \frac{[NH_3]^2}{[NO_2]^2[H_2]^7}$$
$$K_p = \frac{P_{NH_3}^2}{P_{NO_2}^2P_{H_2}^7}$$
(b) $$K_c = \frac{[SO_2]^2}{[O_2]^3}$$
$$K_p = \frac{P_{SO_2}^2}{P_{O_2}^3}$$
(c) $$K_c = \frac{[CO]^2}{[CO_2]}$$
$$K_p = \frac{P_{CO}^2}{P_{CO_2}}$$
(d) $$K_c = \frac{[C_6H_5COO^-][H^+]}{[C_6H_5COOH]}$$
Work Step by Step
The $K_p$ expression follows this pattern:
$$K_p = \frac{P_{products}}{P_{reactants}}$$
Where the exponent of each partial pressure is equal to the balance coefficient of the compound.
The $K_c$ expression is very similar, but it uses the concentration of the compounds, and every compound that is not in the form of a pure solid or a pure liquid appear on the expression.
If there is not any compound in the gaseous form, the $K_p$ is not applicable.
