Answer:
Ketone
Explanation:
As you are stating here, we have a carbonated chain of three carbons, and the first and last has 3 Hydrogens, then this means that we have CH₃ . The center carbon is a carbon double bonded to oxygen.
In general terms this belongs to the carbonyl group. However, this alone does not represent a functional group, but when it's in a chain with other radycals or chains, it becomes a functional group.
In this case, the molecule you are talking here is the following:
CH₃ - CO - CH₃
This molecule is known as the Acetone, and has the general form of:
R - CO - R'
Which belongs to a ketone as a functional group.
