Learn > Functional Groups

Functional Groups

Note: This is a learning resource and may simplify some concepts for educational purposes.

Why Functional Groups Matter

They determine chemical reactivity (how the molecule behaves).
They affect polarity and solubility (whether it dissolves in water or oil).
They influence biological activity (how drugs interact with the body).

What are Functional Groups?

Functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules. The same functional group will undergo the same or similar chemical reactions regardless of the size of the molecule it is a part of.

1. Hydrocarbons

Alkanes (C-C)

Saturated hydrocarbons with single bonds. Unreactive.

Example: View Alkanes

Alkenes (C=C)

Unsaturated hydrocarbons with double bonds. Rigid.

Example: View Alkenes

Alkynes (C≡C)

Unsaturated hydrocarbons with triple bonds.

Example: View Alkynes

Arenes (Aromatic)

Cyclic structures like Benzene with stabilized electron rings.

Example: View Arenes

2. Halogen-Containing

Alkyl Halides (R-X)

Alkane with a halogen substituent (where X = F, Cl, Br, or I).

Example: View Alkyl Halides

3. Oxygen-Containing

Alcohols (R-OH)

Hydroxyl group attached to a carbon.

Example: View Alcohols

Ethers (R-O-R)

Oxygen atom bonded to two carbons.

Example: View Ethers

Aldehydes (R-CHO)

Carbonyl group at the end of a chain.

Example: View Aldehydes

Ketones (R-CO-R)

Carbonyl group in middle of chain.

Example: View Ketones

Carboxylic Acids (-COOH)

Acidic functional group.

Example: View Acids

Esters (-COO-)

Often fragant. Derivative of CA.

Example: View Esters

Amides (-CONH₂)

Amino group bonded to carboxyl C.

Example: View Amides

4. Nitrogen-Containing

Amines (-NH₂)

Derivatives of ammonia (NH₃).

Example: View Amines

Nitriles (-C≡N)

Contain a cyano group.

Example: View Nitriles

Nitro Compounds

Contain a nitro group.

Example: View Nitro

5. Sulfur-Containing

Thiols (-SH)

Sulfur analogue of alcohols. Strong odor.

Example: View Thiols

Sulfides (Thioethers)

Sulfur analogue of ethers (R-S-R).

Example: View Sulfides

6. Phosphorus-Containing

Phosphate Esters

Essential in biochemistry (DNA, ATP).

Example: View Phosphates

7. Special Groups

Acetals

Carbon bonded to two -OR groups.

Example: View Acetals

Next Topic Polarity & Solubility →