NEET Practice Questions (MCQs) with Answers & Solutions

Ethers are classified as simple or symmetrical if the alkyl or aryl groups attached to the oxygen atom are the same, and mixed or unsymmetrical if the two groups are different. In $\\text{C}_2\\text{H}_5\\text{OCH}_3$, the groups are ethyl and methyl, which are different, making it an unsymmetrical ether. $\\text{CH}_3\\text{OCH}_3$ and $\\text{C}_2\\text{H}_5\\text{OC}_2\\text{H}_5$ are symmetrical ethers. $\\text{C}_6\\text{H}_5\\text{OCH}_3$ is also an unsymmetrical ether, but the question asks 'which of the following', and $\\text{C}_2\\text{H}_5\\text{OCH}_3$ is explicitly mentioned as an example of an unsymmetrical ether in the text.

The context states that Benzene-1,3-diol is commonly known as Resorcinol.

According to Table 7.2, Methyl n-propyl ether has the IUPAC name 1-Methoxypropane. In IUPAC nomenclature for ethers, the smaller alkyl group combined with oxygen is named as an alkoxy group (methoxy), and the larger alkyl chain serves as the parent hydrocarbon (propane).

The NCERT text states: 'The longest carbon chain (parent chain) is numbered starting at the end nearest to the hydroxyl group.'

For naming polyhydric alcohols, the 'e' of alkane is retained and the ending 'ol' is added, with multiplicative prefixes (di, tri, etc.) and appropriate locants. HO–CH2–CH2–OH is named as ethane–1,2-diol. Ethylene glycol is its common name.

The text states: 'Common names of ethers are derived from the names of alkyl/aryl groups written as separate words in alphabetical order and adding the word ‘ether’ at the end.'

Table 7.2 lists 'Anisole' as the common name for $\text{C}_6\\text{H}_5\\text{OCH}_3$, and its IUPAC name is 'Methoxybenzene'. While Methyl phenyl ether is also a valid common name, Methoxybenzene is the specific IUPAC name provided.

A primary alcohol has the -OH group attached to a carbon atom that is bonded to only one other carbon atom. CH3CH2CH2OH (n-Propyl alcohol or Propan-1-ol) fits this description. CH3CH(OH)CH3 is secondary, (CH3)3COH is tertiary, and CH2=CH-CH2OH is an allylic alcohol (but specifically a primary type of allylic alcohol, yet the most general primary example is the straight-chain alcohol).

The text states: 'These alcohols contain —OH group bonded to a carbon-carbon double bond, i.e., to a vinylic carbon or to an aryl carbon. These alcohols are also known as vinylic alcohols.'

According to Table 7.1, 2-Methylpropan-2-ol is commonly known as tert-Butyl alcohol.