Question

Which of the following is not a factor involved in determining the rate of a chemical reaction? the fraction of collisions which occur with a favorable orientation the total number of collisions per unit time the fraction of collisions with energy greater than the activation energy the molar mass of the reactants

Answer 1

According to collision theory, for reaction to take place, the reactant molecules must collide. Only those collisons which possses energy greater than activation energy are called fruitful collisions and give rise to product. Hence fraction of collisions determine the rate of reaction. since rate depends on no of collisions, the no of collisiolns per unit time decide the rate of reaction. Howver, the rate of reaction does not depend upon molar mass. For example , the rate of reaction of production of ammonia is less because ammonia is gas even though its molar mass is less. While the rate of reaction between ethyl acetate and sodium hydroxide is more even though the molar mass of ethyl acetate and sodium hydroxide are more than NH3. ( D is correct)