Final answer:
To balance the unbalanced chemical equation Nal + Cl2 → NaCl + 12, place the coefficient 2 in front of the NaCl to balance the chloride ions.
Step-by-step explanation:
In order to balance the unbalanced chemical equation Nal + Cl2 → NaCl + 12, we need to ensure that the same number and types of atoms appear on both sides of the equation. In this case, there are twice as many chloride ions in the reactants than in the products. To balance the chloride ions, we need to place the coefficient 2 in front of the NaCl. Therefore, the balanced equation becomes:
2 Nal + Cl2 → 2 NaCl + 12