What are chemical formulas and the role of subscripts in them?
Chemical formulas are the chemists short hand for molecules.
Instead of writing out the words Magnesium Chloride the chemist simply uses the formula
For the molecule Calcium Phosphate the chemist writes
This formula tells us that there are 3 atoms of Calcium attached to 2 molecules of the polyatomic ion phosphate which has 1 Phosphorus attached to 4 oxygen atoms.
I hope this was helpful.