now answer 15-22 15 the number is missing

When the concentrations of the reactants are increased, the rate of the reaction increases. This is best explained by a. an increase in the fraction of molecules that have enough energy to react. b. an increase in the frequency of the molecular collisions. c. an increase in the rate constant. d. an increase in the kinetic energy of the molecules. e. an increase in the average potential energy of the molecules. 16. Carbon tetrachloride reacts with oxygen at high temperatures to produce chlorine and carbonyl chloride. 2CCH(g) + 02(8) = 2COCI2(g) + 2C12(g) Kc = 1.9 x 1019 What is Kc for the following? COCI2(g) + Cl2(8) = CCI(g) + ; 02(8) a. 5.3 x 10-20 b. 2.3 x 10-10 c. 4.4 x 109 d. -1.9 x 1019 e. 1.9 x 1010 17. The hydronium-ion concentration of a 0.050 M lactic acid solution is 2.62 x 10". The acid dissociation constant is 1.37 x 104. The pH of this lactic acid solution is a. 0.42. b. 1.30. c. 2.58. d. 3.86. e. 5.94. 18. In an experiment, 0.400 mol H2 and 0.400 mol 12 are mixed in a 1.00-L container, and the reaction forms HI. If Kc = 49. for this reaction, what is the equilibrium concentration of HI? 12(g) + H2(g) =2HI(g) a. 0.090 M b. 0.18 M c. 0.31 M d. 0.62 M e. 0.83 M 19. For the following reaction systems at 500 K I. 2NOCI(g) =2NO(g) + Cl2(g) Kp = 1.7 x 10-2 II. 2NO2(8) 2NO(g) + 02(8) Kp = 5.9 x 10-5 III. 2SO3(8) 2802(8) + 02(8) Kp = 1.3 x 10-5 the reactions tendency to go to completion increases in the order a. I