Question

Which of the following is an example of non-biodegradable detergent?
A:

B:

C:

D: $C{H_3} - {\left( {C{H_2}} \right)_{10}} - C{H_2} - OS{O_2}Na$

Answer 1

Hint:Biodegradable substances are the substances which can be decomposed by the action of microorganisms. Non-biodegradable substances are the substances which are not decomposed by the action of microorganisms.

Complete answer:
Surfactants are the compounds that lower the surface tension between two liquids, gas, and a liquid or between a liquid and a solid. Surface tension is defined as the property of the surface of a liquid that allows it to resist an external force. It is the tension of the surface film of a liquid caused by the attraction of the particles in the surface layer by the bulk of the liquid. Surfactants may act as detergents, emulsifiers, foaming agents. Detergent is a surfactant or mixture of surfactants that contain cleansing properties. It is formed from a long chain alkyl group. General formula of detergents is $RSO_4^ - N{a^ + }$. Like soap, these contain both hydrophilic parts and hydrophobic parts. More number of branches will require more energy for dissociation. So detergent which will contain the maximum number of branches will be non-biodegradable. Among given options, detergent in option C has a maximum number of branches. So answer to this question is option C that is:

Answer to this question is option C.

Additional information:} Soap is basically sodium and potassium salt of long-chain fatty acid $RCO{O^ - }N{a^ + }$ . The end of the molecule to which the sodium ion is attached is polar in nature that means it will dissolve in water as water is also polar in nature. As it is dissolved in water it is called the hydrophilic part means water loving. The alkyl chain is nonpolar hence it does not dissolve in water. Due to this reason, it is called hydrophobic part which means water-hating.

Note:
Branched alkyl groups do not dissociate easily as it becomes difficult to break a number of bonds. Detergents are basically long-chain alkyl groups. So basically compounds with more branches will be difficult to dissociate and will be non-biodegradable.