Energy Changes And Reversable Reactions Flashcards
What does an endothermic reaction do?
Take in energy from the surroundings.
What does a exothermic reaction do?
Transfer energy to the surroundings.
What are reversible reactions?
Reversible reactions are where the products can react to remake the original reactants. If the forward reaction is exothermic, the reverse reaction is endothermic.
When a chemical reaction occurs…
Energy is transferred to or from the surroundings - and there is often a temperature change.
Exothermic reactions transfer energy to the surroundings. The energy is usually transferred as…
heat energy, causing the reaction mixture and its surroundings to become hotter.
Some examples of exothermic reactions are…
Combustion (burning)
Many oxidation reactions, for example rusting
Neutralisation reactions between acids and alkalis
Exothermic reactions can be used for everyday purposes. For example…
hand warmers and self-heating cans for drinks (such as coffee) use exothermic reactions.
Endothermic reactions are reactions that take in energy from the surroundings. The energy is usually transferred as…
heat energy, causing the reaction mixture and its surroundings to get colder. The temperature decrease can also be detected using a thermometer.
Name examples of endothermic reactions.
Electrolysis
The reaction between ethanoic acid and sodium carbonate
The thermal decomposition of calcium carbonate in a blast furnace
Endothermic reactions can be used for everyday purposes. For example…
certain sports injury cold packs use endothermic reactions.
In reversible reactions, the reaction in one direction will be exothermic and the reaction in the other direction will be…
endothermic.
