Double Bond between addjacent carbon atoms

C=C

Triple Bonds between adjacent carbons.

-C≡C-

Contain a benzyne ring.

6 carbon atoms, 6 hydrogen atoms

C6H5-

Contains a Hydroxyl functional group

-OH

Oxygen Atom bonded to two carbon atoms

-C-O-C-

EG: CH3-O-CH3

-SH bonded to a carbon atom

-SH

EG: CH3-SH

Carbonyl group (C=O) attached to at least one hydrogen

                                        O 

                                        ||

                                       -C-H

Carbon of the carbonyl (C=O) group attached to 2 other carbon atoms

                                        O 

                                        ||

                                       -C- 

Carboxyl group (carbonyl group (C=O) attached to a hydroxyl (-OH) group)

                                        O 

                                        ||

                                       -C- O-H

Carboxyl Group (carbonyl group C=O attached to a hydroxyl group -OH) between two carbon atoms

                                        O 

                                        ||

                                       -C- O- 

Functional group is a nitrogen atom.  Nitrogen atom with one or more carbon groups.

|

-N-

EG: CH3-NH2

Hydroxyl group (-OH) group of a Carboxylic acid (carbonyl group C=O attached to a hydroxil group (-OH) is replaced with a nitrogen group

                                        O 

                                        ||  |

                                       -C- N-