Calcium Hydroxide and Sulfuric Acid

Ca(OH)2 + H2SO4 → CaSO4 + 2H2O

Overview

Calcium hydroxide reacts with sulfuric acid to form calcium sulfate and water. The product calcium sulfate is a sparingly soluble salt that partially precipitates. This reaction produces gypsum (calcium sulfate dihydrate), one of the most important construction materials.

Participants

Role Substance Coefficient State
Reactant Calcium Hydroxide Ca(OH)₂ 1 (s)
Reactant Sulfuric Acid H₂SO₄ 1 (aq)
Product Calcium Sulfate CaSO₄ 1 (s)
Product Water H₂O 2 (l)

Everyday Example

Gypsum board (drywall) used in virtually every modern building is made from calcium sulfate, which can be produced by this type of reaction.

Industrial Importance

Calcium sulfate (gypsum) is used in drywall, plaster, cement retarder, and as a food additive. Flue gas desulfurization uses lime to react with SO2, producing gypsum as a byproduct.

Properties

Type
Double Replacement
Reversible
No
Energy
Exothermic
ΔH
-109.0 kJ/mol

Related Reactions

Aluminum Hydroxide and Hydrochloric Acid Ammonia and Hydrochloric Acid (White Smoke) Barium Chloride and Sodium Sulfate Precipitation Calcium Carbonate and Hydrochloric Acid Calcium Chloride and Sodium Carbonate Calcium Hydroxide and Carbon Dioxide (Limewater Test) Copper(II) Sulfate and Sodium Hydroxide Iron(III) Chloride and Sodium Hydroxide Lead Nitrate and Potassium Iodide (Golden Rain) Magnesium Hydroxide and Hydrochloric Acid (Antacid)

Frequently Asked Questions

What is the equation for Calcium Hydroxide and Sulfuric Acid?
The balanced equation is: Ca(OH)₂ + H₂SO₄ → CaSO₄ + 2H₂O.
What type of reaction is Calcium Hydroxide and Sulfuric Acid?
Calcium Hydroxide and Sulfuric Acid is a double replacement reaction.
Is Calcium Hydroxide and Sulfuric Acid exothermic or endothermic?
Calcium Hydroxide and Sulfuric Acid is exothermic (releases energy). The enthalpy change (ΔH) is -109.0 kJ/mol.