Question

Which functional group always occurs at the terminal position of a carbon chain?

Answer 1

We must know that the functional groups are groups or specific substituent, functional groups are the responsible for the chemical reactions characteristic of those molecules. Regardless of the size of the molecule the same functional group will undergo the same chemical reaction. Functional groups also give a certain physical and chemical properties.

Complete answer:
We must know that for the specific chemical reactions of that molecule, the functional group is responsible for that molecule. To make a compound new and have desirable properties, the addition of some functional groups are given those properties and it is called functionalization.
We must have to remember that a functional group attached at the end of the carbon chain (terminal position) is called the terminal functional group. If it is not attached at the end of the carbon chain then it is not an end functional group. In functional groups, carbonyl groups must be placed in the terminal position.
If a functional group composed of $C = O$ is called a carbonyl group. Examples of carbonyl group functional groups are carboxylic acids, aldehydes, ketones and esters.
We also know that the carboxylic acids $( - COOH)$ and aldehydes $( - CHO)$ are the functional groups which always occur at the end of the carbon chain.

Note:
We must remember that the functional groups have an important role in organic chemistry for controlling and directing the reactions, also the properties of the compound changes for different functional groups placed. Ketone contains the carbonyl at the inside of the compound but aldehydes are at the terminal positions. Both ketone and aldehyde oxidized to give the corresponding carboxylic acids respectively. Carboxylic acid is the precursor for other functional groups such as esters, ketones and aldehydes.