Chemical Reactions in Laundry Detergents

• Laundry detergents contain substances such as sodium carbonate (Na2CO3) that remove calcium and magnesium ions from the water.

• The dissolved carbonate ions react with calcium and magnesium ions in the hard water to form solid calcium carbonate (CaCO3) and solid magnesium carbonate (MgCO3).

• These solids settle to the bottom of the laundry mixture, resulting in the removal of the ions from the water.

• Laundry detergents contain substances that react with the ions in hard water to immobilize them.

• Reactions such as these—that form solid substances in water—are precipitation reactions.