Question

Iodine value is related to ___.
A- Fats and oils
B- Alcohols
C- Esters
D- Hydrocarbons

Answer 1

Hint: Organic compounds containing special functional groups react with iodine. The amount of iodine that reacts with a given amount of organic compound is called iodine value. Try to identify which of the given functional group-containing compounds react with iodine.

Complete step by step answer:
We know that organic compounds react with iodine which is having some functional group. Iodine value is the amount of iodine needed to react 100 gm with a given organic compound. Hydrogen iodide is used to react with unsaturated hydrocarbons. Unsaturation is measured by reacting with hydrogen iodide.
Interhalogen compounds such as iodine chloride or iodine bromide can also be used to measure the degree of unsaturation in a hydrocarbon. The reaction will be:
\[R-CH=CH-R_{ 1 }\quad +\quad I_{ 2 }\quad →\quad R-CHI-CHI-R_{ 1 }\quad \]
In daily life, we consume fats and oils often. Fats and oils are a long chain of hydrocarbons with many functional groups. There may be an unsaturation in fat and oils. This unsaturation is not good for your health. So we need to measure the degree of unsaturation of different types of fats and oils. For measuring this unsaturation we need to use this iodine value method. We first introduce an excess amount of iodine and then titrate the remaining amount to calculate the amount of iodine reacted.

Hence, the correct answer is option A.

Note:
Other halogen compounds can also be used to react with unsaturated hydrocarbons but Iodine compounds can be easily differentiated as they form a yellow color solution. Saturated hydrocarbons do not react with iodine.