An aldehyde as well as a ketone can be represented by the same molecular formula,say $C_{3}H_{6}O$. Write their structures and name them. State the relation between the two in the language of science.

(N/A) For the molecular formula $C_{3}H_{6}O$,the two isomers are:
$1$. Propanal (Aldehyde): The structure is $CH_{3}-CH_{2}-CHO$.
$2$. Propanone (Ketone): The structure is $CH_{3}-CO-CH_{3}$.
Relation: These two compounds are functional isomers because they possess the same molecular formula but contain different functional groups (aldehyde group $-CHO$ and ketone group $>C=O$).