Magnesium Hydroxide and Hydrochloric Acid (Milk of Magnesia)

Mg(OH)₂ + 2HCl → MgCl₂ + 2H₂O

Overview

Magnesium hydroxide (milk of magnesia) neutralizes hydrochloric acid to form magnesium chloride and water. As a sparingly soluble base, magnesium hydroxide provides sustained acid neutralization without causing rebound acidity. It works gradually as the solid slowly dissolves and reacts.

Participants

Role	Substance	Coefficient	State
Reactant	Magnesium Hydroxide Mg(OH)₂	1	(s)
Reactant	Hydrochloric Acid HCl	2	(aq)
Product	Water H₂O	2	(l)

Everyday Example

Milk of magnesia is a common over-the-counter antacid and laxative, its white milky appearance coming from suspended magnesium hydroxide particles.

Industrial Importance

Magnesium hydroxide is used as an antacid, fire retardant in plastics, and in wastewater treatment for heavy metal precipitation and pH adjustment.

Properties

Type: Acid-Base
Reversible: No
Energy: Exothermic
ΔH: -108.0 kJ/mol

Related Reactions

Acetic Acid and Sodium Acetate Buffer System Acetic Acid and Sodium Hydroxide Neutralization Acetic Acid Dissociation in Water Aluminum Chloride and Chloride Ion (Lewis Acid-Base) Aluminum Hydroxide as Amphoteric Acid with NaOH Aluminum Hydroxide as Amphoteric Base with HCl Ammonia and Ammonium Chloride Buffer System Ammonia and Hydrochloric Acid Ascorbic Acid and Sodium Hydroxide Barium Hydroxide and Ammonium Thiocyanate (Endothermic)

Frequently Asked Questions

What is the equation for Magnesium Hydroxide and Hydrochloric Acid (Milk of Magnesia)?

The balanced equation is: Mg(OH)₂ + 2HCl → MgCl₂ + 2H₂O.

What type of reaction is Magnesium Hydroxide and Hydrochloric Acid (Milk of Magnesia)?

Magnesium Hydroxide and Hydrochloric Acid (Milk of Magnesia) is a acid-base reaction.

Is Magnesium Hydroxide and Hydrochloric Acid (Milk of Magnesia) exothermic or endothermic?

Magnesium Hydroxide and Hydrochloric Acid (Milk of Magnesia) is exothermic (releases energy). The enthalpy change (ΔH) is -108.0 kJ/mol.