Question

Palmitic acid is-
A. $C_{16}H_{31}COOH$
B. $C_{17}H_{35}COOH$
C. $C_{15}H_{31}COOH$
D. $C_{17}H_{31}COOH$

Answer 1

Hint: Biochemistry is one of the important branch of chemistry and fatty acids are one of the important part of biochemistry. Fatty acids are carboxylic acids containing a saturated or unsaturated aliphatic chain.

Complete Step-by-step answer:
Fatty acids are carboxylic acids of the aliphatic chain. Fatty acids occur naturally and they are synthetic as well. Fatty acids are divided on the basis of their length and saturation and the number of carbons in the chain (even or odd).
Examples of fatty acids are-
Saturated fatty acids-
Stearic acid – $CH_3(CH_2)_{16}COOH$
Capric acid – $CH_3(CH_2)_8COOH$
Cerotic acid – $CH_3(CH_2)_{16}COOH$
Unsaturated fatty acids-
Palmitoleic acid – $CH_3(CH_2)_5CH=CH(CH_2)_7COOH$
Vaccenic acid –$ CH_3(CH_2)_5CH=CH(CH_2)_9COOH$
Oleic acid – $CH_3(CH_2)_7CH=CH(CH_2)_7COOH$

The formula of palmitic acid is $CH_3(CH_2)_{14}COOH$ it contains an aliphatic chain of 15 carbons connected to a carboxylic acid. Palmitic acid is one of the important components of oil mainly palm oil. It is a major component of the animal body. Palmitic acid is also used as a surfactant, it is used in the preparation of soaps and detergents. On hydrogenation, palmitic acid produces cetyl alcohol. Salt of palmitic acid sodium palmitate is used as a natural additive in food products.
Thus, Option (C) is correct

Note: Stearic acid is also one of the most important fatty acids. It is also found in animal fat but less in vegetable fat. It is obtained by the process of saponification. In Surfactant and softening agents, stearic acid is one of the major component. It is also used as a food additive, soap, cosmetics, and detergent. For lubrication sodium salt of stearic acid (sodium stearate) is used. Lithium stearate is a major component of grease.