1.3 Exothermic & Endothermic Reactions

Question 1

What is an exothermic reaction?

Answer 1

An exothermic reaction is one which gives out energy to the surroundings. This is usually shown by a rise in temperature of the surroundings. The products have less energy than the reactants

Question 2

What is an endothermic reaction?

Answer 2

An endothermic reaction is one which takes in energy from the surroundings. This is usually shown by a fall in temperature of the surroundings. The products have more energy than the reactants

Question 3

What are reaction profiles used for?

Answer 3

Reaction profiles show the energy levels of the reactants and the products in a reaction. You can use them to work out if energy is released (exothermic) or taken in (endothermic)

Question 4

What is activation energy?

Answer 4

The activation energy is the minimum amount of energy needed for bonds to break and a reaction to start. For example, you need to provide energy before fuel will burn.

Question 5

How is activation energy shown on a reaction profile?

Answer 5

On a reaction profile, the activation energy is the difference between the reactants and the highest point on the curve