IUPAC= International Union of Pure and Applied Chemistry

• Prefix: Something that is attached before or at the beginning. There are two types of prefixes.
  • Primary Prefix: Helps distinguish between a cyclic and an acyclic compound. The prefix Cyclo is used for cyclic compounds only.
  • Secondary Prefix: Certain groups in organic Chemistry are written as prefixes. They are regarded as substituents, e.g -F = Fluoro, -Cl = Chloro, -Br = Bromo, -I = Iodo
• Word Root: It is the name corresponding to no. of carbon atoms in the longest chain of Carbon atoms in the organic compound. e.g C$_1$ = Meth, C$_2$ = Eth, C$_3$ = Prop C$_4$ = But, etc.
• Primary Suffix: It indicates the nature of carbon atom chain selected. e.g. Only single bond between C-atoms = -ane, double bond = -ene, triple bond = -yne. If the parent chain contains two, three or more double or triple bonds, then the numerical prefixes such as di(for two), tri(for three), tetra (for four) atc. are added to the primary suffix. If both double and triple bonds are present, then '-ene' comes before '-yne'.
• Secondary suffix: This is the word that defines the 'family' or functional in an organic compound.e.g. -COOH is Carboxylic Acids, suffixed as -oic acid, -COOR is esters suffixed by -oate and -COX is Acyl Halides suffixed by -oyl halide.

• Prefix: 3-Methyl
• Word Root: but
• Primary Suffix: ene
• Secondary suffix: ol

Solved Example: 9110-01

Which one of the following is the general formula of Alkenes? (DSSSB TGT Natural Science Sep 2021 Shift II)

A. $C_nH_n$

B. $C_nH_{2n}$

C. $C_nH_{2n+1}$

D. $C_nH_{2n+2}$

Correct Answer: B

Solved Example: 9110-02

The substituent in the chain is named by replacing the “ane” in the alkanes by:

A. ene

B. ic

C. one

D. yl

ene, ic and one are used for representing alkenes, carboxylic acids, and ketones respectively, hence yl is the term which is to be substituted in place on ane in the alkanes.

Correct Answer: D

Solved Example: 9110-03

Triple bond with two carbon atoms on either side is called:

A. Methnyl group

B. Ethynyl group

C. Propionyl group

D. Propargyl group

Triple bond with two atoms on either side are called as ethynyl group and those with one carbon on one side and two carbon on another side are called as propargyl group.

Correct Answer: B

Solved Example: 9110-04

Which of the following is an aldehyde? (SSC CGL Jun 2019 Shift II)

A. Propanal

B. Propanol

C. Propine

D. Propanone

Correct Answer: A

Solved Example: 9110-05

______ is a saturated hydrocarbon. (RRC Group D Oct 2018 Shift III)

A. Acetylene

B. Propene

C. Ethene

D. Ethane

Correct Answer: D

Solved Example: 9111-01

Which of the following represents Alkenes? (RRC Group D Oct 2018 Shift II)

A. -C = C-

B. -C - C-

C. H - O - H

D. O = C = O

Correct Answer: A

Solved Example: 9109-01

Which one of the following chemical equations is balanced?

A. 2NaCl + H$_2$SO$_4$ → HCl + NaSO$_4$

B. 2Na + S → 2NaS

C. KOH + H$_2$SO$_4$ → KHSO$_4$ + H$_2$O

D. NH$_3$ + H$_2$O → 2NH$_4$OH

Correct Answer: C