The collision theory is that particles must collide, and with sufficient energy, in order to react.

The minimum energy that the particles must have in order to react is known as the activation energy.

Rate of reaction is the speed with which a chemical reaction takes place, measured by the amount of a reactant used or amount of product formed in a given time.

Collision theory

Combined science

In the Industrial Chemistry unit, pupils will build on their knowledge of reaction rates to learn about the industrial processes involving chemical reactions and the factors that affect them.

In the Energy Changes in Reactions unit, pupils learned about bond breaking, bond making, and reaction profiles.

Rate of reaction

Which conditions must particles of reactants meet in order to react in a chemical rection?

How does increasing the surface area of a solid affect the rate of reaction?

it increases the size of the reactant particles

it decreases the number of successful collisions

it increases the number of successful collisions

it decreases the speed of reactant particles

it increases the frequency of successful collisions

Why does increasing the concentration of reactants typically increase the rate of reaction?

the reactant particles are more likely to collide

there are more reactant particles in the same volume

What happens when the concentration of a reacting solution is increased?

more particles have energy higher than the activation energy

What effect does decreasing the pressure of reacting gases have on the rate of reaction?

it increases the kinetic energy of particles

it increases the number of particles exposed on the surface of a solid reactant

What effect does increasing the temperature of reactants have on the rate of reaction?

In the following reaction identify the reactant: hydrogen peroxide → water + oxygen

Which solution has the highest concentration?

It is the speed with which a chemical reaction takes place.

It can be measured by the amount of reactant used × time taken.

It can be measured by the amount of reactant used ÷ time taken.

It can be measured by the amount of product formed.

It can be measured by the amount of product formed × time taken.

Which of the following statements about rate of reaction are true?

increase the density of the calcium carbonate

A student has 5 g of calcium carbonate. How can they increase the surface area of the calcium carbonate?

the rate of reaction is not affected by the variable

On a volume versus time graph, what does a steep gradient represent?

particles must collide, and with sufficient energy, in order to react

the minimum energy that the particles must have in order to react

the amount of chemical dissolved in a certain volume of solution

is the total area of every outer surface of an object 

Match the key term to the correct definition.

This lesson will be removed by end of Summer Term 2025.

Collision theory

Lesson outcome

This lesson will be removed by end of Summer Term 2025.