17. In which of the following reactions does the reaction mixture at equilibrium contain predominantly reactants? (a) I2(g) + Br2(g) (b) I2(g) 2 IBr(g) Kp = 118; 2 I(g) Kc = 3.1×10-5; (c) 2 SO2(g) + O2(g) 2 SO3(g) Kp = 2.5×109.