Question

Write any two observations that can be made, when soap is added to the sample of hard water and write two reasons for your observations.

Answer 1

1) Hardwater doesn't produce form with soap easily
Because,
Soaps contain Na & K salt of long chain fatty acids . When they are dissolved in hard water (which contains Ca & Mg ions) , these ions replace the Na & K from their salt to form insoluble Ca & Mg salts of fatty acids these insoluble salts separate as scum.

2C17H35COONa + CaCl2 → 2NaCl + (C17H35COO)2Ca

2)they tend to get “ring around the tub” and other than Ca and Mg minerals deposits in their sinks and bath tubs.
beacuase,
Ca and mg are insoluble salts it produce scum
The other minerals are soluble in water