Question
Explain why soaps become inactive in hard water.
✓
Answer
$i.$ Soaps form scum in hard water and become inactive.
$ii.$ This is because, hard water contains dissolved salts of calcium and magnesium. Soaps react with these salts to form insoluble calcium and magnesium salts of fatty acids.
$iii.$ This insoluble substance is termed as scum which sticks to the fabric.
$iv.$ Reaction of soap with calcium salt $(CaCl_2)$ from hard water is given below:
$ii.$ This is because, hard water contains dissolved salts of calcium and magnesium. Soaps react with these salts to form insoluble calcium and magnesium salts of fatty acids.
$iii.$ This insoluble substance is termed as scum which sticks to the fabric.
$iv.$ Reaction of soap with calcium salt $(CaCl_2)$ from hard water is given below:
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