how do you find how many atoms are in each chemical formula?

Question

or example magnesium chloride or mgcl2. how do i find the 2 chlorine atoms and can you please show me steps how to do it because how does +2 atom go with 2, -1 atoms to make Mgcl2

Answer 1

oxidation no of Mg is +2and that of Cl is -1
Since a compound should be electrically neutral, -2 neg charge is requred to balance +2 charge of Mg ion.
Thus 2 radicals of chlorine combine with a single Mg ion to form MgCl2.

u should learn the concept of valency rather than asking!