Question

The active ingredient in Milk of Magnesia™ is Mg(OH)2. Magnesium hydroxide is insoluble in water, so the product is a mixture of water, flavoring, and other ingredients to suspend the solid Mg(OH)2. When someone suffering from acid indigestion takes this drug, the Mg(OH)2 reacts with the HCl in the stomach. Classify this chemical reaction and write a balanced equation. (Include states of matter)

Answer 1

Answer:  This chemical reaction is a neutralization reaction between the Milk of Magnesia and the HCl from the stomach. The balanced equation is Mg(OH)2 (s) + 2 HCl (aq) → MgCl2 (aq) + 2 H2O (l)

Explanation:

The reaction between the HCl and the  Mg(OH)2 is a neutralizacion reaction ,  because the HCl is a strong acid and the  Mg(OH)2 is a weak base, then both react and the pH of the medium will increase, so the stomach trouble will dissapear.

Mg(OH)2 (s) + 2 HCl (aq) → MgCl2 (aq) + 2 H2O (l)

Magnesium hydroxide is a weak base due to its very limited solubility in water. This property is a great advantage when treating the excess of HCl in the stomach, because the Mg(OH)2 molecule does not dissociated  easily until it reacts with the  hydrogen ion, H+ of the HCl. So the effect of the  Mg(OH)2 will last longer until the annoyance dissapear.