Give a suitable reason why detergents are used even in case the water contains ca and my ions
Answers
Detergents is the sodium salt of a long chain Benzene Suplhonic acid which has cleansing properties in water.
A detergent has a large non ionic hydrocarbon group and an ionic group like sulphonate group, SO³⁻ Na⁺.
Examples of detergents are :
Sodium n-dodecyl benzene sulphonate and sodium n-dodecyl sulphate
Cleansing action of detergent is same as soap.
Merits of using Detergent :
1. detergents can be used even with hard water where as soaps are not suitable for use with hard water.
2. Detergents have stronger cleansing action than soaps.
3. detergents are more soluble in water than soaps.
Demerits of using Detergents:
1. Detergents are not biodegradable that is they cannot be composed by micro organisms like bacteria
2. Detergents causes water pollution .
Reason for the having calcium and magnesium ions :
Detergents react with with Ca²⁺ and Mg²⁺ ions in hard water forming soluble compounds. lather is formed easily and cleansing action is efficient.