Question

Water which doesn't give lather immediately with soap is called soft water.

• A. True
• B. False

Answer 1

Answer: (B)

Soaps are basically sodium salt of fatty acids.

In the presence of excess calcium and magnesium ions in water, the sodium ions are replaced by these ions and are precipitated as scum.

Water containing an excess of these (calcium and magnesium) ions is called hard water.

Therefore option $B$ is correct.