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Chemical equations - AQA SynergyChemical formulae of elements

Chemists use symbols and formulae to represent elements and compounds. Word equations and balanced chemical equations represent the changes that happen in chemical reactions.

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Chemical formulae of elements

A chemical is used to represent an or in .

The formula for most elements is just its chemical symbol. For example:

  • helium, He
  • lithium, Li
  • beryllium, Be
  • boron, B
  • carbon, C
  • neon, Ne
  • sodium, Na
  • magnesium, Mg

Some non-metal elements exist as that are made up of two joined together. The formulae of these elements are the element's symbol followed by a '2'. For example:

  • iodine, I2
  • bromine, Br2
  • chlorine, Cl2
  • fluorine, F2
  • oxygen, O2
  • nitrogen, N2
  • hydrogen, H2

A can be used to remember these elements:

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Question

What are the chemical formulae of the elements neon, nitrogen and sodium?