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Chemical equation

In chemistry, a chemical equation is a symbolic representation of a chemical reaction. For example, the combustion of methane in oxygen is

CH4 + 2 O2 → CO2 + 2 H2O,

and the reversible reaction of the Haber process is

N2(g) + 3H2(g) ↔ 2NH3(g) + ΔH.

How do you read chemical equations?

The first number in a set such as 3H2O tells how many molecules of the substance there is. The number in subtext following the element tells how many atoms of the element there are. The letters represent elements from the Periodic table.

ex. 3H2O means 3 molecules, each containing 2 parts Hydrogen, 1 part Oxygen.

See also

Last updated: 06-02-2005 02:53:55
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