Answer:
Step-by-step explanation:
Chemical formulae tells the kind of atoms and their relative proportion in a compound.
For this purpose, chemical formulae use chemical symbols and numbers.
Each element has a chemical symbol. For example, H is used for hydrogen, O is used for oxygen, Na is used for sodium, C is used for carbon.
Numbers as subscripts to the right of a chemical symbol means the number of atoms of that element in the compound.
These are some examples:
Compound chemical meaning
formula
Sodium chloride NaCl the unit fomula NaCl is formed by 1
atom of sodium and 1 atom of chlorine.
Water H₂O the molecule H₂O (water) is formed by
2 atoms of hydrogen and 1 atom of oxygen.
Methane CH₄ the molecule CH₄ is formed by 1 atom of
carbon and 4 atoms of hydrogen.
In those examples you see how chemical symbols and numbers, which is the chemical formulae, are used to represent the substances.