To determine the number of each atom on the reactant side of the equation [tex]\(3 \text{Mg(OH)}_2 + 2 \text{H}_3 \text{PO}_4\)[/tex], let's break it down step by step:
1. Consider the contribution of each compound:
- For [tex]\(3 \text{Mg(OH)}_2\)[/tex]:
- Magnesium (Mg): Each molecule of [tex]\(\text{Mg(OH)}_2\)[/tex] contains 1 Mg atom. Since there are 3 molecules, we have [tex]\(3 \times 1 = 3\)[/tex] Mg atoms.
- Oxygen (O): Each molecule has 2 oxygen atoms (from the [tex]\((OH)_2\)[/tex] part), which gives [tex]\(3 \times 2 = 6\)[/tex] oxygen atoms.
- Hydrogen (H): Each molecule has 2 hydrogen atoms (again from the [tex]\((OH)_2\)[/tex] part), resulting in [tex]\(3 \times 2 = 6\)[/tex] hydrogen atoms.
- For [tex]\(2 \text{H}_3 \text{PO}_4\)[/tex]:
- Hydrogen (H): Each molecule of [tex]\(\text{H}_3 \text{PO}_4\)[/tex] contains 3 hydrogen atoms. Hence, [tex]\(2 \times 3 = 6\)[/tex] hydrogen atoms.
- Phosphorus (P): Each molecule contains 1 phosphorus atom. Consequently, [tex]\(2 \times 1 = 2\)[/tex] phosphorus atoms.
- Oxygen (O): Each molecule has 4 oxygen atoms, leading to [tex]\(2 \times 4 = 8\)[/tex] oxygen atoms.
2. Sum up the number of atoms for each element on the reactant side:
- Magnesium (Mg): [tex]\(3\)[/tex] atoms
- Phosphorus (P): [tex]\(2\)[/tex] atoms
- Oxygen (O): [tex]\(6\)[/tex] (from [tex]\(\text{Mg(OH)}_2\)[/tex]) + [tex]\(8\)[/tex] (from [tex]\(\text{H}_3 \text{PO}_4\)[/tex]) = [tex]\(14\)[/tex] atoms
- Hydrogen (H): [tex]\(6\)[/tex] (from [tex]\(\text{Mg(OH)}_2\)[/tex]) + [tex]\(6\)[/tex] (from [tex]\(\text{H}_3 \text{PO}_4\)[/tex]) = [tex]\(12\)[/tex] atoms
Therefore, the correct listing of the numbers of each atom that the other half of the equation would contain is:
[tex]\[ \text{3 Mg, 2 P, 14 O, 12 H} \][/tex]
Thus, the correct answer is:
[tex]\[ 3 \, \text{Mg} , 2 \, \text{P} , 14 \, \text{O} , 12 \, \text{H} \][/tex]
