5.1.1

Energy Conservation

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Energy Transfer/Conservation

In chemical reactions, energy is not created or destroyed. It is conserved (saved) and transferred between objects. Chemical reactions are exothermic or endothermic, depending on the energy transfers that happen:

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Exothermic reactions

  • Energy from the reacting chemicals is transferred to the surroundings, which often increase in temperature as a result. Examples include:
    • Combustion.
    • Neutralisation.
    • Oxidation.
Illustrative background for Endothermic reactionsIllustrative background for Endothermic reactions ?? "content

Endothermic reactions

  • Energy from the surroundings is transferred to the reacting chemicals, causing the temperature of the surroundings to decrease. Examples include:
    • Thermal decomposition.
    • The reaction that happens when citric acid is combined with sodium hydrogen carbonate (sodium bicarbonate).

Jump to other topics

1States of Matter

2Atoms, Elements & Compounds

3Stoichometry

4Electrochemistry

5Chemical Energetics

6Chemical Reactions

7Acids, Bases & Salts

8The Periodic Table

9Metals

10Chemistry of the Environment

11Organic Chemistry

11.1Formulae, Functional Groups & Terminology

11.2Naming Organic Compounds

11.3Fuels

11.4Alkanes

11.5Alkenes

11.6Alcohols

11.7Carboxylic Acids

11.8Polymers

12Experimental Techniques & Chemical Analysis

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