Temperature Change
When a chemical reaction occurs, energy is transferred to, or from, the surroundings - and there is often a temperature change. For example, when a bonfire burns it transfers heat energy to the surroundings. Objects near a bonfire become warmer. The temperature rise can be measured with a thermometer.
Exothermic reactionsThese are reactions that transfer energy to the surroundings. The energy is usually transferred as heat energy, causing the reaction mixture and its surroundings to become hotter. The temperature increase can be detected using a thermometer. Some examples of exothermic reactions are:
Exothermic reactionsThese are reactions that transfer energy to the surroundings. The energy is usually transferred as heat energy, causing the reaction mixture and its surroundings to become hotter. The temperature increase can be detected using a thermometer. Some examples of exothermic reactions are:
- burning
- neutralisation reactions between acids and alkalis
- the reaction between water and calcium oxide
- electrolysis
- the reaction between ethanoic acid and sodium carbonate
- the thermal decomposition of calcium carbonate in a blast furnace