Magnesium carbonate, magnesium oxide, and magnesium hydroxide are all white solids that react with acidic solutions. (a) Write a balanced molecular equation and a netionic equation for the reaction that occurs when each substance reacts with a hydrochloric acid solution. (b) By observing the reactions in part (a), how could you distinguish any of the three magnesium substances from the other two?

1. Reaction of magnesium carbonate (MgCO3) with hydrochloric acid (HCl): Balanced molecular equation: MgCO3 (s) + 2HCl (aq) -> MgCl2 (aq) + H2O (l) + CO2 (g) Net ionic equation: MgCO3 (s) + 2H^+ (aq) -> Mg^2+ (aq) + H2O (l) + CO2 (g) 2. Reaction of magnesium oxide (MgO) with hydrochloric acid (HCl): Balanced molecular equation: MgO (s) + 2HCl (aq) -> MgCl2 (aq) + H2O (l) Net ionic equation: MgO (s) + 2H^+ (aq) -> Mg^2+ (aq) + H2O (l) 3. Reaction of magnesium hydroxide (Mg(OH)2) with hydrochloric acid (HCl): Balanced molecular equation: Mg(OH)2 (s) + 2HCl (aq) -> MgCl2 (aq) + 2H2O (l) Net ionic equation: Mg(OH)2 (s) + 2H^+ (aq) -> Mg^2+ (aq) + 2H2O (l)

In each of these reactions, we can identify some differences that would help us distinguish one magnesium substance from the others: 1. Magnesium carbonate (MgCO3) - This substance produces carbon dioxide (CO2) gas when reacting with hydrochloric acid. The formation of gas can be observed as bubbles or fizzing during the reaction. 2. Magnesium oxide (MgO) - This substance does not produce any gas when reacting with hydrochloric acid, making it distinct from the magnesium carbonate. However, it is similar to magnesium hydroxide in this aspect. 3. Magnesium hydroxide (Mg(OH)2) - To distinguish magnesium hydroxide from magnesium oxide, we can observe the solubility in water. Magnesium hydroxide is slightly soluble in water, forming a milky solution when mixed. On the other hand, magnesium oxide is nearly insoluble in water. By looking at the solubility of the substances in water, we can differentiate magnesium hydroxide from magnesium oxide. In summary, to distinguish the three magnesium substances from each other, we can observe the formation of gas during the reaction with hydrochloric acid (which indicates the presence of magnesium carbonate), and the solubility of the substances in water to differentiate magnesium hydroxide from magnesium oxide.