Chemical reaction

Rusting iron

A bonfire is an example for redox.

A chemical reaction happens when one or more chemicals are changed into one or more other chemicals. Examples:

• iron and oxygen combining to make rust
• vinegar and baking soda combining to make sodium acetate, carbon dioxide and water
• things burning or exploding
• many reactions that happen inside living things

Some reactions are very fast, and others are very slow. Some happen at different speeds, depending on temperature or other things. For example, wood does not react with air when it is cold, but if it is made hot enough, it will start to burn.

Some reactions give out energy. These are called exothermic. In other reactions, energy is taken in. These are called endothermic.

Equations

A chemical reaction is being displayed by a equation:

$\mathrm{ A + B \longrightarrow C + D}$

Here, A and B react to C and D in a chemical reaction.

Example

$\mathrm{C + O_2 \longrightarrow CO_2}$

carbon + oxygen → carbon dioxide

Other websites

• Rates of reaction
• Online Chemical Equation Balancer Balances equation of any chemical reaction (full or half-cell) in one click.