Chemistry

Chemical Nomenclature

95 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

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.
Multiple choice nomenclature of ethers alcohols, phenols and ethers chemistry

$\displaystyle C _{6}H _{5}-O-C _{7}H _{15}\left ( n \right )$ IUPAC name of the compound is :

  1. 1-Phenoxyheptane

  2. 1-Heptoxybenzene

  3. Both (a) and (b)

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

here, phenoxy group ($\displaystyle C _{6}H _{5}-O-$) is attached with heptane so its name is 1-Phenoxyheptane

Multiple choice nomenclature of ethers alcohols, phenols and ethers chemistry

IUPAC name of the given compound is: 

$CH _3-O-CH _2-CH(CH _3)-CH _3$

  1. $1-$Methoxy$-2-$methylpropane
  2. $2-$Methylpropane-methane

  3. both (A) and (B)

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

The IUPAC names of the following compounds 1-Methoxy-2-methylpropane. Here methoxy group is taken as substituent.

Multiple choice nomenclature of ethers alcohols, phenols and ethers chemistry

IUPAC name of  $\displaystyle CH _{3}CH _{2}CH _{2}OCH _{3}$ is:

  1. 1-Methoxypropane

  2. 1-Propoxymethane

  3. both (A) and (B)

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

$CH _3CH _2CH _2OCH _3$

3       2        1
IUPAC name for the above compound is 1-methoxy propane.
So answer is A.

Multiple choice nomenclature of ethers alcohols, phenols and ethers chemistry

The IUPAC name of $C _{2}H _{5} O C _{2}H _{5}$ :

  1. Diethyl ether

  2. Ethoxy ethane

  3. Ethoxy propane

  4. Dimethyl ether
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The molecule C2H5-O-C2H5 is diethyl ether, which is named systematically as ethoxyethane. The prefix ethoxy- represents the C2H5O- group, and the ethane suffix represents the remaining two-carbon chain.

Multiple choice nomenclature of ethers alcohols, phenols and ethers chemistry

According to the IUPAC rules in naming of ether the two alkyl groups attached to the oxygen are put in :

  1. alphabetical order

  2. the larger group (R) is chosen as the parent hydrocarbon

  3. both A and B

  4. none of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
In IUPAC rules of naming others, larger alkyl or aryl group (R) is chosen as the parent hydrocarbon and when in writing, all substituents are arranged in alphabetical order.
Example: $CH _3-O-C _2H _5$, the name of this compound will be methoxy ethane.
Multiple choice nomenclature of ethers alcohols, phenols and ethers chemistry

According to the IUPAC nomenclature ethers are regarded as hydrocarbon derivatives in which a hydrogen atom is replaced by an :

  1. alkoxy group

  2. alkyl group

  3. carbonyl group

  4. epoxy group
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
In IUPAC nomenclature of ethers, a hydrogen atom is replaced by $-OR$ (alkoxy group) or $-OAr$ (aryloxy group)
Example: $CH _3-O-CH _3$ is an ether which is obtained by replacing one hydrogen atom from methane with methoxy group ($-OCH _3$). Thus, the ether will be named as methoxymethane.