Chemistry Written Test Questions for IIT JEE Exam on “Alcohols, Phenols and Ethers Nomenclature – 2”.
1. What is the correct name of the following compound?
a) But-3-enol
b) But-3-en-2-ol
c) But-1-en-3-ol
d) But-2-en-3-ol
Answer: b
Clarification: The numbering preference is given to the hydroxyl group over the double bond and hence, the OH lies on the second carbon and double bond on the third.
2. What is the correct IUPAC name of the following phenol?
a) Benzene-1,2,4-triol
b) 1,2,4-Benzenetriol
c) Benzene-1,2,4-triphenol
d) 1,2,4-Triphenol
Answer: a
Clarification: Polyhydric phenols are named as hydroxy derivatives of benzene in the IUPAC system. The positions 1,2,4 comply with the lowest set of locants rule.
3. What is the correct common name of 2-Bromophenol?
a) 2-Bromophenol
b) m-Bromophenol
c) o-Bromophenol
d) 2-Hydroxybromobenzene
Answer: c
Clarification: Phenol is used as the common as well as the IUPAC name and haloarenes with hydroxy groups are named as halo derivatives of phenols.
4. Which of the following is given highest preference while naming when present in the same structure?
a) Hydroxyl group
b) Nitro group
c) Triple bond
d) Halogen group
Answer: a
Clarification: Functional groups are given the highest preference while naming compounds according to the IUPAC system.
5. What is the correct common name for CH3OC2H5?
a) Methyl methyl ether
b) Methyl ethyl ether
c) Ethyl ethyl ether
d) Ethyl methyl ether
Answer: d
Clarification: It is an unsymmetrical ether with one methyl group and one ethyl group. It is named such that the alkyl group are in alphabetical order.
6. Which of the following compounds is ethoxyethane?
a) CH3OCH3
b) CH3OC2H5
c) C2H5OC2H5
d) C2H5OC3H7
Answer: c
Clarification: Ethoxyethane is an ether which is a derivative of ethane with one hydrogen atom replaced by ethoxy group (OC2H5).
7. Identify the incorrect name for CH3-O-C6H5.
a) Methyl phenyl ether
b) Methoxybenzene
c) Anisole
d) Phenetole
Answer: d
Clarification: This is an aromatic ether with a methoxy substituent and has the common name anisole or methyl phenyl ether.
8. What is the IUPAC name of CH3-O-CH2-CH2-OCH3?
a) 1,2-Dimethoxyethane
b) 1,3-Dimethoxybutane
c) 2,3-Dimethoxyethane
d) 1,4-Dimethoxypropane
Answer: a
Clarification: The base hydrocarbon is ethane, in which one hydrogen of each carbon atom is replaced by a methoxy group, making it a dimethoxy ether.
9. What is the IUPAC name of CH3(CH2)6-OC6H5?
a) Heptyl phenyl ether
b) 1-Phenoxyheptane
c) 1-Hepoxybenzene
d) Phenyl heptyl ether
Answer: b
Clarification: Since heptane is a larger group than benzene, it is chosen as the parent hydrocarbon and the compound is named as an aryloxy derivative of heptane.
10. The name 1-Ethoxy-2, 2-dimethylcyclohexane is correct according to IUPAC nomenclature.
a) True
b) False
Answer: b
Clarification: The methyl group should be given higher preference over the alkoxy group in ethers. The correct naming will be 2-Ethoxy-1, 1-dimethylcyclohexane.
11. Phenetole is an aromatic ether.
a) True
b) False
Answer: a
Clarification: Phenetole is also known as ethoxybenzene or ethyl phenyl ether and has an aromatic ring on one side.
Chemistry Written Test Questions for IIT JEE Exam,