Match the name or structure with its functional group. Each molecule has only one functional group.

My choices are alkane, alcohol, alkyne, carboxylic acid, alkene, aldehyde, ketone, ester, and ether.
1. 2-propanol- alcohol
2. 2-methoxypentane- alkane
3. formaldehyde- aldehyde
4. acetone- ketone
5. 3-hexanone- ketone
6. 1-bromo-2-cyclononene- alkene
I am sure that numbers 1,4,5,6 are right but not sure on numbers 2 and 3

All are ok except 2. 2 is an ether.

To determine the functional group of each molecule, you need to understand the general formulas and characteristics of each functional group. Here's a breakdown of the compounds you mentioned:

1. 2-propanol: This is an alcohol because it contains the -OH functional group.

2. 2-methoxypentane: This compound has an oxygen atom connected to a pentane chain. Since it doesn't have any functional groups other than the alkane chain, it is indeed an alkane.

3. Formaldehyde: This compound has the formula CH2O. It contains a carbonyl group (C=O), which is the characteristic functional group of aldehydes. Therefore, formaldehyde is indeed an aldehyde.

4. Acetone: It has the formula (CH3)2CO. The carbonyl group (C=O) is present, which indicates a ketone functional group. Therefore, acetone is a ketone.

5. 3-hexanone: This compound also contains a ketone functional group because it has a carbonyl group (C=O) in its structure.

6. 1-bromo-2-cyclononene: This particular compound isn't mentioned in the options you provided, but based on its name, it is a cyclic compound and contains a double bond (ene) and a bromine atom. Therefore, it is an alkene.

In summary, the functional groups of the compounds you mentioned are as follows:

1. 2-propanol - alcohol
2. 2-methoxypentane - alkane
3. Formaldehyde - aldehyde
4. Acetone - ketone
5. 3-hexanone - ketone
6. 1-bromo-2-cyclononene - alkene