Question

Preserving food by freezing controls reaction rates by

A) decreasing the number of collisions
B) increasing concentration
C) changing the number of effective reactant collisions
D) both a and c are correct

Answer 1

Answer:

D) both a and c are correct

Explanation:

The reaction rate is a measure of the speed of a chemical reaction. The factors that affects the rate of a chemical reaction are itemised below:

• Nature of the reactants
• Concentration of the reactants or pressure(if gaseous)
• Temperature
• Presence of catalyst
• Sunlight

Our concern here is temperature. Temperature affects a reaction considerably. Average kinetic energy is directly proportional to the temperature of the reacting particles. When the temperature of a reacting system is increase, the frequency of ordinary and effective collisions per unit time increases. A decrease in temperature implies that the number of collisions also decreases.