Question

Give the structural formula of the following:
1-Propanal.

Answer 1

Hint: Aldehydes are the functional group of 1-propanal. It is an organic compound which has an aldehyde (-CHO) functional group to its structure.

Complete step by step answer:
> Aldehyde is a compound which contains -CHO as the functional group. It consists of a carbonyl center, which is a double-bonded carbon to oxygen, with that carbon also bonded to a hydrogen and to an R group, which is any alkyl or side chain.
> Aldehydes are always attached at the start or the end of the structure. It can be added in between the chain but then it has to be on a branched carbon which is not further attached to any group. They can be either unsaturated, that is they contain carbon-carbon double bonds, or can be saturated. An aldehyde ends with a prefix "-al", like methanal, ethanal, propanal, butanal, etc.
The structure of an aldehyde is given below.

> Now, let us look at the structural formula of 1-propanal. "Prop" means that the compound has three carbon atoms in its structure. The -al as a prefix suggests that it is an aldehyde. And the '1' in its name suggests the position where the aldehyde group is present in the formula, that is on the first carbon. The structural formula is given as:

Since propane has a symmetrical structure. Therefore, it does not matter if the aldehyde group is attached at the start of the chain or the end of the chain. The place of the group will remain the same from both sides.

Note: There is a difference between an aldehyde and a ketone. An aldehyde contains -CHO as a functional group. But ketone contains -CO- as a functional group, with a carbon-oxygen double bond. Ketone can only be added in between the chain whereas an aldehyde is added only at the start or end of the chain.