Rates Of Reaction

Question 1

How do you measure rate of reaction?

Answer 1

The rate at which the reactant is used up

The rate at which the product is formed

Question 2

What factors affect the rate of reaction?

Answer 2

Temperature 
Concentration 
Pressure of reacting gases 
Surface area of reacting solids 
Use of a catalyst

Question 3

Why do chemical reactions happen?

Answer 3

When reactant particles collide with enough energy.

The more frequently particles collide, the greater the amount of successful collisions the greater the rate of reaction

Question 4

What is the equation for rate of reaction?

Answer 4

Amount of reactant used or amount of product formed/ time taken

Question 5

Why may a graph showing rate of reaction be steeper at the start?

Answer 5

It is happening faster because the concentration of reactant is the biggest

Question 6

Why does concentrations affect the rate of reaction?

Answer 6

There are more reactant particles in the same volume, there is a greater chance of the particles colliding which means more successful collision and a greater rate of reaction

Question 7

Why does surface area affect the rate of reaction?

Answer 7

More particles are exposed to the reactants
There is a greater chance of the particles colliding
The rate of reaction increases

Question 8

Why does temperature affect the rate of reaction?

Answer 8

The particles have more energy so move more quickly
More particles have the activation energy
The particles collide more often and with more energy so the rate of reaction increases

Question 9

Why does a catalyst increase the rate of reaction?

Answer 9

Increases the rate of reaction without being used up
Catalyst lower the activation energy
More collisions result in a reaction
Rate of reaction increases

Question 10

Why does pressure affect the rate of reaction?

Answer 10

There are more particles in the same volume
Greater chance of them colliding
Increased rate of reaction