Worksheet for identifying functional groups in organic molecules.

This is a chemistry activity sheet asking you to group molecules based on their functional groups. The goal is to identify the key structural feature (the functional group) that defines the chemical behavior of each molecule, rather than focusing on the length of the carbon chain.

I will analyze each molecule and group them accordingly.

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Step 1: Identify Functional Groups

First, I need to recognize the common functional groups present in organic chemistry. Based on the instructions, I'll focus on the atoms or groups attached to the carbon chain and the types of bonds.

Common functional groups visible here include:
- Alcohol (-OH): A hydroxyl group bonded to a carbon.
- Ether (-O-): An oxygen atom bonded to two carbon atoms.
- Aldehyde (-CHO): A carbonyl group (C=O) at the end of a carbon chain, with one H attached to the carbonyl carbon.
- Ketone (>C=O): A carbonyl group bonded to two carbon atoms.
- Carboxylic Acid (-COOH): A carbonyl group bonded to a hydroxyl group.
- Ester (-COOR): A carbonyl group bonded to an oxygen, which is then bonded to another carbon.
- Amine (-NH₂, -NHR, -NR₂): A nitrogen atom bonded to carbon(s) and/or hydrogen(s).
- Amide (-CONH₂, -CONHR, -CONR₂): A carbonyl group bonded to a nitrogen atom.

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Step 2: Analyze Each Molecule

I will now go through each lettered molecule and classify it.

#### Group 1: Alcohols (-OH)
These have an -OH group attached to a saturated carbon.
- B: Ethanol (CH₃CH₂OH)
- C: Propanol (CH₃CH₂CH₂OH)
- F: Butanol (CH₃CH₂CH₂CH₂OH)
- N: Propanoic acid? Wait, no, N has a carboxylic acid group. Let me re-examine.

Actually, N has a carboxylic acid group. Let's correct that.

- B, C, F are alcohols.

#### Group 2: Ethers (-O-)
An oxygen atom connected to two alkyl groups.
- A: Dimethyl ether (CH₃OCH₃)
- E: Diethyl ether (CH₃CH₂OCH₂CH₃)
- G: Another ether, likely diethyl ether or similar.
- Q: This looks like an ester. Let me check.

Wait, Q has a carbonyl and an ether linkage — that’s an ester.

So, ethers are:
- A, E, G

#### Group 3: Aldehydes (-CHO)
Carbonyl at the end of the chain with H.
- D: Formaldehyde (HCHO)
- H: Acetaldehyde (CH₃CHO)
- U: Propanal (CH₃CH₂CHO)

#### Group 4: Ketones (>C=O)
Carbonyl in the middle of the chain.
- I: Butanone (CH₃COCH₂CH₃)
- K: Pentanone? Or acetone? K is CH₃COCH₂CH₃? Wait, let's see.

Actually, K is CH₃COCH₂CH₃ — that’s butanone, same as I? No, I is also butanone? Let me check the structures.

Looking again:
- I: Has a carbonyl between two carbons — ketone.
- K: Also has a carbonyl between two carbons — ketone.

Yes, both are ketones.

#### Group 5: Carboxylic Acids (-COOH)
- M: Acetic acid (CH₃COOH)
- T: Formic acid (HCOOH)
- N: Propanoic acid (CH₃CH₂COOH)

#### Group 6: Esters (-COOR)
- O: Methyl acetate (CH₃COOCH₃)
- P: Ethyl propanoate? Or something similar — has ester linkage.
- Q: Methyl propanoate? Has ester group.

Yes, O, P, Q are esters.

#### Group 7: Amines (-NH₂, -NHR, -NR₂)
- J: Ethylamine (CH₃CH₂NH₂)
- S: Methylamine (CH₃NH₂)
- R: This has a carbonyl and NH — that’s an amide.

Wait, R is an amide.

So, amines are:
- J, S

#### Group 8: Amides (-CONH₂)
- L: Acetamide (CH₃CONH₂)
- R: N-methylacetamide? Or formamide? R is H₂N-C(=O)-CH₃? Wait, R is CH₃-C(=O)-NH₂? No, R is drawn as CH₃-C(=O)-NH-H, so it’s acetamide.

Actually, L is formamide (HCONH₂), and R is acetamide (CH₃CONH₂).

Both are amides.

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Step 3: Organize into Groups

Now, I will list the molecules by their functional group.

#### Alcohols
- B, C, F

#### Ethers
- A, E, G

#### Aldehydes
- D, H, U

#### Ketones
- I, K

#### Carboxylic Acids
- M, T, N

#### Esters
- O, P, Q

#### Amines
- J, S

#### Amides
- L, R

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Final Answer

Here is the grouping of molecules based on their functional groups:

| Functional Group | Molecules |
|-----------------------|---------|
| Alcohol | B, C, F |
| Ether | A, E, G |
| Aldehyde | D, H, U |
| Ketone | I, K |
| Carboxylic Acid | M, T, N |
| Ester | O, P, Q |
| Amine | J, S |
| Amide | L, R |

This classification is based on the key functional group present in each molecule, as instructed. The number of carbon atoms was not the primary criterion; instead, the type of functional group and the bonding pattern were used for grouping.