1.5 - Kinetics

Question 1

What must particles do in order to react?

Answer 1

Collide with sufficient energy (activation energy) and the correct orientation.

Question 2

Do most collisions result in a reaction?

Answer 2

No

Question 3

Define activation energy.

Answer 3

The minimum energy requied for a reaction to take place.

Question 4

What is the effect of increasing temperature on rate of reaction? Why?

Answer 4

• Increasng temperature increases the rate of reaction.
• Much higher proportion of particles have energy greater than the activations energy -> many more successful collisions per second -> increased rate.

Question 5

What is the effect of increasing concentration and pressure on the rate of reaction? Why?

Answer 5

• Increases concentration/pressure -> increased rate of reaction.
• There are more particles in a given volume -> more frequent successful collisions -> increased rate.

Question 6

What is a catalyst?

Answer 6

A substance which increases the rate of reaction but is not used up in the reaction.

Question 7

How do catalysts work and how do they increase the rate of reactions?

Answer 7

• Provide an alternative reaction pathway (one with lower activation energy).
• Lowers activation energy, so more frequent successful collisions, so increased rate.