3 b) Rates of Reaction

Question 1

Catalyst

Answer 1

Substance that speeds up a chemical reaction by providing an alternative pathway of lower activation energy. Catalysts are not used up and remain chemically unchanged at the end of the reaction.

Question 2

Collision theory

Answer 2

Reactant particles must collide with each other and the collision needs to have sufficient energy and the correct orientation for a reaction to occur.

Question 3

Dependent variable

Answer 3

What you measure in an experiment.

Question 4

Independent variable

Answer 4

What you vary in an experiment.

Question 5

Rate

Answer 5

The speed at which the amount of reactants decreases or the amount of products increases. It is measured as a change in the concentration (or amount) per unit time.

Question 6

Activation energy

Answer 6

Minimum amount of energy required to result in a reaction (successful collision).

Question 7

Anomalous result

Answer 7

A result that does not fit in with the pattern of the others.

Question 8

Kinetic energy

Answer 8

A form of energy a substance possesses due to motion.

Question 9

Tangent

Answer 9

A straight line that touches a curve, but does not cut across it.