Question

which of the following statements is incorrect? question 30 options: the slow step in a mechanism generally involves a three-body collision. a three-body collision is less likely than a two-body collision. after the addition of a catalyst, the collision rate between molecules is still the same. most collisions between reactant molecules do not lead to a product. chemical reactions involve collisions between the participating molecules.

Answer 1

The incorrect statement is that catalysts do not change the collision rate between molecules. Catalysts increase reaction rates by lowering activation energy, thus affecting the frequency of effective collisions.

Step-by-step explanation:

The statement that is incorrect is: "After the addition of a catalyst, the collision rate between molecules is still the same." This statement is false because while a catalyst does not alter the equilibrium concentrations of reactants and products, it does increase the rate at which the reactants are converted into products by providing a new pathway with a lower activation energy for the reaction, which can increase the frequency of effective collisions.

It is true that the slow step in a mechanism generally involves a three-body collision, which is termed as being part of a termolecular reaction and is indeed very slow due to the low likelihood of three reactants simultaneously colliding. A three-body collision is less likely than a two-body collision. Additionally, most collisions between reactant molecules do not lead to a product because in many collisions, molecules simply bounce off each other without any reaction taking place, due to insufficient kinetic energy or incorrect orientation during the collision. Also, chemical reactions indeed involve collisions between the participating molecules as part of the collision theory of reaction rates.