Factors affecting rates of reaction

Question 1

What 4 things can affect the rate of reaction?

Answer 1

Temperature
Concentration/pressure
Surface area
Catalyst

Question 2

Why does increasing the temperature increase the rate of reaction?

Answer 2

1. Temp increase
2. Particles move faster
3. More collisions which have enough energy to make the reaction happen

Question 3

Why does increasing the concentration or pressure increase the rate?

Answer 3

1. If a solution is more concentrated then there are more particles in the same volume of liquid
2. If pressure increases there is a smaller space for the same amount of particles to occupy
3. This all makes collisions more frequent

Question 4

How does increasing the surface area increase the rate of reaction?

Answer 4

If one of the reactants is a solid then breaking it up into smaller pieces will increase the surface area to volume ratio

Question 5

What is a catalyst?

Answer 5

A substance that speeds up a reaction without being used up itself

Question 6

How does a catalyst work?

Answer 6

They decrease the activation energy and provide an alternative reaction pathway