Verified Solution • 2025–26 Session
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QJEEM08Ch1cb0: JEE Main 2008 Chemistry - Class 11 JEEM08Ch1cb0 Solution: The correct decreasing order of priority for the functional…
The correct decreasing order of priority for the functional groups of organic compounds in the IUPAC system of nomenclature is
Multiple Choice Options
- A −COOH, −SO3H, −CONH2, −CHO
- B −SO3H, −COOH, −CONH2, −CHO
- C −CHO, −COOH, −SO3H, −CONH2
- D −CONH2, −CHO, −SO3H, −COOH
Step-by-Step Verified Solution
The correct order of priority for the given functional group is
| Functional group (priority order) | suffix(s) | prefix | |
|---|---|---|---|
| (1) |  | Oic acid(when carbon(C) of this functional group present in the main chain) or Carboxylic acid (when carbon(C) of this functional group is not present in the main chain) | Carboxy |
| (2) |  | sulphonic acid | sulpho |
| (3) |  | Oic anhydrid (when carbon(C) of this functional group present in the main chain) or Carboxylic anhydride (when carbon(C) of this functional group is not present in the main chain) | |
| (4) |  | Oate (when carbon(C) of this functional group present in the main chain) or Carboxylate (when carbon(C) of this functional group is not present in the main chain) | |
| (5) |  | Oyl halide (when carbon(C) of this functional group present in the main chain) or Carboxyl halide (when carbon(C) of this functional group is not present in the main chain) | haloflormyl |
| (6) |  | amide (when carbon(C) of this functional group present in the main chain) or carbamide (when carbon(C) of this functional group is not present in the main chain) | carbamoyl |
| (7) | cynide ( | nitrile (when carbon(C) of this functional group present in the main chain) or carbonitrile (when carbon(C) of this functional group is not present in the main chain) | cyano |
| (8) |  | Carbylamine | isocyano |
| (9) |  | al (when carbon(C) of this functional group present in the main chain) or Carbaldehyde (when carbon(C) of this functional group is not present in the main chain) | formyl (oxo) |
| (10) |  | one | oxo |
| (11) | ol | hydroxy | |
| (12) | thiol | mercapto | |
| (13) | amine | amino |
From this table you can see -COOH has highest priority and -NH2 has lowest priority among all functional groups.