Determine if most reactants or products will exist at equilibrium based on the magnitude of the equilibrium constant.

a. N_2(g) + O_2(g) 2 NO_(g) K_c = 1.5 X 10^-10

b. 2 SO_2(g) + O_2(g) 2 SO₃(g) Kc = 6.1 10¹⁰

c. 2 NO(g) + O₂(g) 2 NO₂(g) Kc = 1.2 10¹⁴

d. 2 HBr(g) H₂(g) + Br₂(g) Kc = 5.8 10^-18

d. 2 HBr_(g) H_2(g) + Br_2(g) K_c = 5.8 10^-18