Chapter 14.2, Problem 1RC

For which of the following reactions is K_c equal to K_P?

(a)     ${\text{4NH}}_3(g)+{\text{5O}}_2(g)\rightleftharpoons \text{4NO}(g)+{\text{6H}}_2\text{O}(g)$

(b)     ${\text{2H}}_2{\text{O}}_2(aq)\rightleftharpoons {\text{2H}}_{\text{2}}\text{O}(l)+{\text{O}}_{\text{2}}(g)$

(c)     ${\text{PCl}}_3(g)+{\text{3NH}}_3(g)\rightleftharpoons \text{3HCl}(g)+\text{P}{({\text{NH}}_2)}_3(g)$