What do the subscripts mean in a chemical formula?

1 Answer
Jun 1, 2014

It indicates that there are a certain number of atoms in a compound.

For example:

#Al_2(SO_4)_3#

This shows that there are three times the number of atoms which are in the brackets:

S - 1 x 3 = 3 atoms
O - 4 x 3 = 12 atoms

Hope this helps!