Consider the reaction: 4NH_3 + 7O_2 rightarrow 4NO_2 + 6H_2O 1. At a certain instant the initial rate of disappearance of the oxygen gas is X. What is the value of the appearance of water at the same instant? A) 1.2 X B) 1.1 X C)0.86 X D) 0.58 X E) cannot be determined from the data For a reaction in which A and B react to form C, the following initial rate data were obtained: What is the rate law? A) Rate = k[A][B] B) Rate = k[A]^2[B] C) Rate = k[A][B]^2 D) Rate = k [A]^2[B]^2 E) Rate = k[A]^3 The reaction 2NO rightarrow N_2 + O_2 has the following rate law. – Delta [NO]/Delta t = 2k[NO]^2 After a period of 2.7 times 10^3 s, the concentration of NO falls from an initial value of 2.8 times 10^-3 mol/L to 2.0 times 10^- 3 mol/L. What is the rate constant, K? A) 1.5 times 10^-7 M^-1 middot s^-1 B) 5.3 times 10^-2 M^-1 middot s^-1 C) 3.2 times 10^-1 middot s^-1 D) 1.2 times 10^-4 M^-1 middot s^-1 E) 2.6 times 10^-2 M^-1 middot S^-1