An exothermic chemical reaction is a type of reaction in which energy is transferred from the reactants to the surroundings e.g. combustion.

An endothermic chemical reaction is a type of reaction in which energy is transferred from the surroundings to the products e.g. photosynthesis.

A solution is formed when a substance dissolves into a liquid.

Calorimetry is an experiment than can be used to measure an energy change during a reaction.

Energy changes in reactions

Chemistry

In the Rate of Reaction unit, pupils will build on their understanding of energy changes to learn about the factors that influence the rate of chemical reactions.

In the Fuels and Energetics unit, pupils learned about energy changes during chemical reactions, including exothermic and endothermic reactions.

Chemical reaction in which energy is transferred to the surroundings.

Chemical reaction in which energy is transferred to the products.

Formed when a substance dissolves in a liquid.

An experiment used to measure energy change during a reaction.

Match the following terms to the correct definition.

Which of the following are examples of exothermic chemical reactions?

After an endothermic reaction, the temperature of the surroundings {{}}.

Which of the following are examples of everyday uses of exothermic reactions?

Barium sulphate, BaSO₄, is a precipitate produced during a chemical reaction. Which state symbols should appear after BaSO₄ in the symbol equation?

A student measured the initial temperature of a reaction as 22°C and the final temperature as 16°C. Which of these statements about the reaction are true?

Match the following state symbols to the correct meaning.

They transfer energy from the surroundings to the products.

They transfer energy from the reactants to the surroundings.

Which of the following statements about exothermic reactions are true?

The hotter an object, the more energy is present in its {{}} store of energy.

Which of the following methods of energy transfer involves only the vibration of particles?

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

Energy changes in reactions

Lesson outcome

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