Chapter 13 - Rates of reaction

Question 1

What is the rate of reaction?

Answer 1

The change of concentration with time.

Question 2

What is the formula for rate of reaction?

Answer 2

Average rate = c2-c1/t2-t2

Question 3

What is catalyst?

Answer 3

A substance that increases the rate of reaction without undergoing permanent chemical change in the reaction.

Question 4

What is a heterogeneous reaction?

Answer 4

Reactions that occur at the interface between two phases, such as between a gas and a solid or between a solution and a solid.

Question 5

What is a homogeneous reaction?

Answer 5

A reaction in which the reactants are present as a homogeneous mixture either as a mixture of gases or as a solution.

Question 6

What are the factors that influence the rate of homogeneous reaction?

Answer 6

• concentration of the reactants
• nature and concentration of any catalyst
• temperature.

Question 7

What does the collision theory of reaction rates propose?

Answer 7

For chemical reaction to occur, the reactant particles must -
- collide
have more than a certain minimum amount of kinetic energy
- be correctly orientated

Question 8

What is activation energy?

Answer 8

The minimum amount of energy reactants must have to undergo reaction.

Question 9

What are enzymes?

Answer 9

Biological catalysts. They are protein that bring about important reactions in all living cells.