Question

How can the rate of a reaction be decreased?

A} having more surface area
B} adding a catalyst
C} lowering the temperature
D} increasing the amount of reactants

Answer 1

To decrease the rate of a chemical reaction, you can choose option C: "lowering the temperature."

Lowering the temperature typically reduces the kinetic energy of the reactant molecules, which results in slower molecular motion and fewer effective collisions between reactant molecules. As a result, the reaction rate decreases.

The other options mentioned can have different effects:

- A: Having more surface area can increase the reaction rate by providing more contact between reactant particles.

- B: Adding a catalyst typically increases the rate of reaction by lowering the activation energy required for the reaction to occur.

- D: Increasing the amount of reactants might initially increase the reaction rate, but it doesn't necessarily decrease it.