Why do soaps not work in hard water?

Vedclass pdf generator app on play store
Vedclass iOS app on app store
(N/A) Soaps are sodium or potassium salts of long-chain fatty acids. Hard water contains calcium $(Ca^{2+})$ and magnesium $(Mg^{2+})$ ions. When soaps are dissolved in hard water,these ions displace sodium or potassium from their salts and form insoluble calcium or magnesium salts of fatty acids. These insoluble salts separate as scum.
$2C_{17}H_{35}COONa + CaCl_2 \to (C_{17}H_{35}COO)_2Ca + 2NaCl$
This is the reason why soaps do not work in hard water.

Explore More

Similar Questions

Which of the following statements are not correct?
$a$) Antihistamine also functions as an antacid
$b$) The shape of an active site of an enzyme does not change when the drug binds to an allosteric site
$c$) Chemical messengers communicate the message between two neurons
$d$) Potassium soaps are hard,while sodium soaps are soft to skin
The correct answer is

Which of the following are produced from coal tar?

$A$ detergent is a

Match List-$I$ with List-$II$ :
List-$I$ (Chemical) List-$II$ (Used as)
$(a)$. Sucralose $(i)$. Synthetic detergent
$(b)$. Glyceryl ester of stearic acid $(ii)$. Artificial sweetener
$(c)$. Sodium benzoate $(iii)$. Antiseptic
$(d)$. Bithionol $(iv)$. Food preservative

Choose the correct match:

$A$ neutral fertilizer among the following compounds is

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo