How many hydrogen atoms are in the molecule of C8H10N4O2?

The subscripts in a chemical formula representing a single molecule, are the numbers of atoms of each atom in one molecule (remember no subscript is understood to be 1. So add the subscripts to get the total number of atoms in one molecule of a substance. 8+10+4+2=24 atoms in a single molecule of C8H10N4O2.