Chemistry

Chemical Nomenclature

67 Questions

Chemical nomenclature focuses on writing standard IUPAC names for organic and inorganic compounds. This topic is essential for chemistry sections across science exams. Regular practice helps in quickly identifying functional groups and structural priority.

organic compound naminginorganic compound namingIUPAC naming rulesfunctional groups

Chemical Nomenclature Questions

Multiple choice

What is the IUPAC name of ethylene?

  1. ethane

  2. ethene

  3. acetylene

  4. none of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Ethylene is the common (trivial) name, while ethene is the systematic IUPAC name following the naming convention for alkenes (suffix -ene). Ethane is an alkane, acetylene is the common name for ethyne, and 'none of these' is incorrect since option B is valid.

Multiple choice

What is the IUPAC name of CH3OH?

  1. methanol

  2. methyl alcohol

  3. ethanol

  4. none of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

CH3OH is methanol, which is the IUPAC name for the simplest alcohol containing one carbon atom. The 'meth-' prefix indicates one carbon, and '-anol' suffix indicates the alcohol functional group.

Multiple choice

What is the IUPAC name of C2H5COOH?

  1. methanoic acid

  2. ethanoic acid

  3. propanoic acid

  4. none of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

C2H5COOH contains three carbon atoms (two in the ethyl group and one in the carboxyl group). According to IUPAC nomenclature for carboxylic acids, a three-carbon acid is called propanoic acid (prop- for three carbons, -anoic acid for carboxylic acid).

Multiple choice

The IUPAC name for Michler's ketone is

  1. (R)-3-methylcyclopentadecanone

  2. 3,5,5-trimethyl-2-cyclohexene-1-one

  3. 2,6-dimethyl-2,5-heptadien-4-one

  4. 4,4-bis(dimethylamino)benzaphenone

  5. Both (1) and (2)
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This option is correct.

Multiple choice

Which of the following pairs of formula and its IUPAC name is mismatched?

  1. [Rh(η5-C5H5)2] : bis(η5-cyclopentadienyl)rhodium(II)

  2. K2[OsCl5N] : potassium pentachloronitridoosmate(III)

  3. Cr(η6-C6H6)2 : bis(η6-benzene)chromium

  4. [Co(NH3)5CO3]Cl : pentaamminecarbonatocobalt(III) chloride

  5. [Cr(H2O)4Cl2]Cl : tetraaquadichlorochromium(III) chloride
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Osmium is in +6 oxidation state in given complex. Hence, the correct IUPAC name of K2[OsCl5N] is potassium pentachloronitridoosmate(VI).

Multiple choice

The IUPAC name of Na3 [CO (NO2)6] is

  1. Sodium Cobaltinitrite

  2. Sodium hexanitro cobalt (III)

  3. Sodium hexanitro cobaltate (III)

  4. Sodium hexa nitrito cobaltate (III)
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The IUPAC name for Na3[Co(NO2)6] is sodium hexanitrocobaltate(III). The metal is in the anionic complex, so it ends in -ate.

Multiple choice

What is the Systematic (IUPAC) name of chloroxylenol ?

  1. 2,2'-sulfanediylbis(4,6-dichlorophenol)

  2. 4-chloro-3,5-dimethylphenol

  3. 2-(4-Methyl- 1-cyclohex- 3-enyl) propan- 2-ol

  4. none of these.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

 4-chloro-3,5-dimethylphenol is the systematic (IUPAC) name of  chloroxylenol, so the given option is correct.

Multiple choice nomenclature of ethers alcohols, phenols and ethers chemistry

 $\displaystyle C _{6}H _{5}-O-C _{2}H _{5}$  


IUPAC name of the compound is :

  1. Ethoxybenzene

  2. Phenoxyethane

  3. Benzoxyethane

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In IUPAC nomenclature for ethers, the smaller alkyl group is named as an alkoxy group attached to the larger alkane chain. Here, the ethoxy group is attached to the benzene ring, making it ethoxybenzene.

Multiple choice nomenclature of ethers alcohols, phenols and ethers chemistry

 The IUPAC name of $CH _3 CH _2OCH _2 \overset{O}{\overset{||}{C}} - H$ is 

  1. Formy methyl ethyl ether

  2. Ethyl aldo methyl ether

  3. 2-ethoxy formate

  4. 2-ethoxy ethanal
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The molecule contains an ether group and an aldehyde group. The aldehyde is the principal functional group, so the chain is numbered starting from the aldehyde carbon. The ethoxy group is at position 2, leading to 2-ethoxyethanal.

Multiple choice nomenclature of ethers alcohols, phenols and ethers chemistry

IUPAC name of the $ CH _3 - O - C _2H _5 $ is:

  1. ethoxymethane

  2. methoxyethane

  3. methylethyl ether

  4. ethylmethyl ether
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
In IUPAC system, ethers are named as alkoxy alkaline. The ethernal oxygen is taken with a smaller alkyl group and forms a part of the alkoxy group while larger alkyl group is considered to be the part of alkyl. 
$CH _3-o-C _2H _5$
Methoxyethane.