Question

how does detergent clean with hard water​

Answer 1

Answer:

As soap is applied to hard water, it reacts with the Ca2+ and Mg2+ ions in the water. Soap's sodium salts are converted to calcium and magnesium salts, which precipitate as scum. Since the insoluble scum adheres to the clothing, soap's cleaning ability is decreased.

Answer 2

when soap is added to ca2+mg2 ions are present in hard water they react with soap