The chemical \(4[NH_4Fe (S O_4)_2 \times 12H ]\) contains how many more hydrogen atoms than oxygen atoms?

Use the given chemical formula to compute the total number of hydrogen atoms and the total number of oxygen atoms. Subscripts attached to an atom in a chemical formula indicate the number of that particular atom. Subscripts attached to a molecule indicate the number of that particular molecule. Coefficients also indicate the number of a particular atom or molecule.
The \(NH_4\) indicates that there are 4 hydrogen atoms per \(NH_4\) molecule. The coefficient of 4 indicates that there are \(4 \times 4 = 16\) hydrogen atoms coming from the \(NH_4\) . This also applies to the 12H to give \(4 \times 12 = 48\) hydrogen atoms. Combining these, there are a total of 64 hydrogen atoms in the chemical.
Apply the same technique to find the total number of oxygen atoms: the \(S O_4\) shows that there are 4 oxygen atoms per \(S O_4\) molecule, and 2 of each of these molecules to give \(4 \times 2 = 8\) oxygen atoms. This is multiplied with the coefficient 4 to give a total of \(4 \times 2 = 8\) oxygen atoms.
Finding the difference: 64−32=32