Question
Why detergents are better cleansing agents than soaps? Explain.
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Answer
A substance capable of removing grease and dirt from any fabric or body is called detergent. The detergents are of two types Le. soapy and non-soapy detergents. The soapy detergents are soaps whereas the non-soapy detergents are synthetic detergents or simply detergents. Although both are cleansing agents, they differ in chemical composition. In the present chapter, we shall briefly discuss the composition and cleansing action of soaps and synthetic detergents.
Soaps are the sodium and potassium salts of long chain fatty acids with general formula RCOONa or RCOOK. The acids present have the formula RCOOH where R may have following values.
| $C _{15} H _{31} COOH$ Palmitic acid $\left(R=C_{15} H_{31}\right)$ |
$C_{17} H_{33} COOH$ Oleic acid $\left(R=C_{17} H_{33}\right)$ |
$C_{17} H_{35} COOH$ $ Stearic acid$ $\left(R=C_{17} H_{35}\right)$ |
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