Rate Of Reaction

Question 1

What is the rate of reaction?

Answer 1

The rate of reaction is the speed at which a reaction takes place.

Question 2

How do you measure the rate of reaction?

Answer 2

. Measure how quickly the reactants are used up.
. Measure how quickly the products are formed.

Question 3

What is needed to happen for a reaction to occur?

Answer 3

For a reaction to happen, the reacting particles must successfully collide.

Question 4

What happens if you increase the rate of reaction?

Answer 4

Increasing the rate of reaction increases the chance/frequency of successful collisions.

Question 5

What are the 4 ways of changing the rate of reaction?

Answer 5

Temperature, concentration, surface area and catalyst.

Question 6

At a higher temeprature the particles have more …… and move faster.

Answer 6

Kinetic energy

Question 7

At a higher pressure there are more …… in the same space. This ….. the chance of successful collisions - so a ….. rate if reaction.

Question 8

What is a catalyst?

Answer 8

A catalyst is a substance that speeds up a reaction without being used up.

Question 9

What does a larger surface are provide?

Answer 9

A larger surface area provides more space for the reacting particles to collide. This increases the chance of successful collisions - sima faster rate of reaction.

Question 10

What is the equation for calculating the mean rate of reaction?

Answer 10

Mean rate = change in quantity divided by the time taken

Question 11

What is the unit for rate of reaction in a reaction involving a change in mass?

Answer 11

g/s

Question 12

What is the unit for rate of reaction in a reaction invloving a change in volume?

Answer 12

cm cubed/s

Question 13

What is the activation energy?

Answer 13

The minimum amount of energy colliding particles have fo have before a reaction will take place.

Question 14

How do catalysts increase the rate of reaction?

Answer 14

It lowers the activation energy of the reaction, so more collisions result in a reaction.

Question 15

What happens when a reaction is in equilibrium?

Answer 15

The rate of the forward reaction is equal to the rate of the reverse reaction.

Question 16

What does decreasing the activation energy do?

Answer 16

Decreasing the activation energy means that more particles will have sufficient energy to overcome the energy barrier and react.

Question 17

What does increasing the concentration of a reaction do?

Answer 17

Increasing the concentration increases the rate of reaction because it makes the particles collide more and more reactant particles are moving together.

Question 18

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

Answer 18

If the surface area of a reactant is increased: more particles are exposed to the other reactant. there is a greater chance of particles colliding, which leads to more successful collisions per second. the rate of reaction increases.