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

Which of the following statement is not correct in the naming of ethers according to IUPAC rules?

  1. Ethers are named as alkoxy alkanes

  2. The numbering of the parent chain is done in such a way so that the carbon atom linked to the -O-atom gets the lowest number.

  3. The two alkyl groups attached to the oxygen are put in alphabetical order

  4. In the case of simple ethers, the prefix tri is attached before the name of the alkyl group.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
If both the alkyl groups attached to the $-O-$ atoms are same, then the prefix 'di' is added before the alkyl group. 
Example: $CH _3-O-CH _3$ is named as dimethyl ether.
Multiple choice nomenclature of ethers alcohols, phenols and ethers chemistry

Which of the following naming is not given correctly?

  1. $C _2H _5 - O - C _2H _5$ is Diethyl ether
  2. $C _6H _5 - O - C _6H _5$ is Diphenyl ether
  3. $C _2H _5 - O - C _6H _5$ is Ethyl phenyl ether
  4. $C _2H _5 - O - C _3H _7$ is Diethyl propylether
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

$C _2H _5$ is ethyl and $C _3H _7$ is propyl. Therefore, the correct common name, arranged in alphabetical order will be Ethyl Propyl Ether.

Multiple choice nomenclature of ethers alcohols, phenols and ethers chemistry

IUPAC name of the compound $CH _3-\underset{\displaystyle CH _3}{\underset{|}CH}-OCH _3$ is:

  1. 1 - methoxy - 1 - methylethane

  2. 2 - methoxy - 2 - methylethane

  3. 2 - methoxypropane

  4. isopropylmethyl ether.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Given molecule: $CH _3-\underset{\displaystyle CH _3}{\underset{|}CH}-OCH _3$

It is an ether $ROR'$. In naming ether, smaller alkyl group among R and R' is treated as side group as alkoxy and the other as alkane along with the position of the alkoxy group. Thus in the given molecule, it is methoxy group at second position of propane (alkane)
$\overset { 1 }{ C } H _{ 3 }-\underset { \overset { 3 }{ C } H _{ 3 } }{ \underset { | }{ \overset { 2 }{ C }  }  }H -OCH _{ 3 }$
Thus its name is: 2-methoxypropane.

Multiple choice chemistry chemical reactions of organic compounds alkanoic acids nomenclature of carboxyl group nomenclature of carboxylic acids

The correct name of the given compound :
${ CH } _{ 3 }-\overset { \underset { | }{ H }  }{ \underset { \overset { | }{ OH }  }{ C }  } -{ COOH }$

  1. glycoxal

  2. lactic acid

  3. glycine

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

The given compound is Lactic acid.

It contain one $-OH$ group and one $-COOH$ group along with 3 carbon atoms.