During the ion exchange process, which ions are exchanged for sodium?

In the ion exchange process, specifically when it comes to the softening of water, calcium and magnesium ions are primarily exchanged for sodium ions. This is because hard water contains high concentrations of calcium (Ca²⁺) and magnesium (Mg²⁺), which contribute to water hardness and can lead to scale buildup in plumbing and appliances.

Ion exchange systems use a resin that is initially saturated with sodium ions. When hard water passes through this resin, the calcium and magnesium ions in the water are attracted to the resin and exchanged with the sodium ions. This effectively removes the hardness-causing ions from the water while releasing sodium ions into it.

This process not only helps improve water quality by reducing hardness but also enhances the efficiency of soap and detergents, which perform better in softer water.