19) Which of the following reactions would you predict to have the smallest orientation factor? B) NOCINO 2NOC D)N+O, NO Solution Answer: Option (B) The smaller the molecules the larger the orientation factor. The larger the molecules the smaller the orientation factor. In option (B) since here the reactants are asymmetrical and must therefore collide in such a way that Nitrogen atom is in close proximity to another Nitrogen atom. Therefore, we expect (B) to have the smallest orientation factor. SMALL ORIENTATION FACTOR: A small orientation factor in which reactants approaches zero means that the orientation requirements for these reactions are very close and strong, such that the molecule has to be aligned in a very specific way for the reaction to occur. k = A e power -E a / RT (Arrhenius equation) where e power = exponential of R is the gas constant: 8.31 J / mol K A is a constant called the frequency factor (or pre exponential factor) E a is the activation energy. In the above equation based on the E a (activation energy) the smallest orientation factor will be determined which indirectly describes about the rate of reaction. .