Exothermic and Endothermic

Question 1

What is an exothermic reaction?

Answer 1

It is where energy from the reacting chemical is transferred to the surroundings, which often increase in temperature as a result.

Question 2

What are some examples of exothermic reactions?

Answer 2

• combustion
• neutralisation
• oxidation

Question 3

What is an endothermic reaction?

Answer 3

It is when energy from the surroundings is transferred to the reacting chemicals, causing the temperature of the surroundings to decrease.

Question 4

What are some examples of endothermic reactions?

Answer 4

• thermal decomposition

- the reaction that happens when citric acid is combined with sodium hydrogen carbonate. (Sodium bicarbonate)

Question 5

Where can we find an example of an exothermic reaction in every day life?

Answer 5

Disposable HAND WARMERS use the energy released by iron oxidation.

On the other hand, reusable hand warmers source their energy from the crystallisation of salt solutions. Boiling the pack re-dissolves the crystals so that it’s ready to be used once more.

Question 6

What is an example of where an endothermic reaction takes place in every day life?

Answer 6

SPORTS INJURY PACKS

• When squeezed forcefully, ammonium nitrate and water mix in the pack, resulting in instant cooling.
• The speed of this reaction makes these packs ideal for scenarios when ice is not immediately available.