Chemistry MCQs for NEET — Practice Questions with Answers

Tautomerism is a phenomenon where a proton migrates between two structural isomers that are in equilibrium with each other. A common example is the keto-enol tautomerism, where a proton shifts between the oxygen and carbon atoms.

The compound $C_4H_{10}O$ can show metamerism (e.g., diethyl ether and methyl propyl ether), functional isomerism (e.g., butanol and methoxypropane), and position isomerism (e.g., 1-butanol and 2-butanol). Thus, it exhibits all these types of isomerism.

Cis-trans isomerism (also known as geometric isomerism) occurs in alkenes where there are two different groups attached to each carbon of the double bond. In $ClCH = CHCl$, the double-bonded carbons each have different groups (H and Cl), allowing for the existence of cis and trans forms.

An open chain compound is a compound with a linear or branched structure and no rings. Pentane, isopentane, and neopentane all have open chain structures. Therefore, the correct answer is 'All the above'.

An unsaturated compound contains at least one double or triple bond between carbon atoms. Therefore, compounds with carbon-carbon double bonds, carbon-carbon triple bonds, or both are considered unsaturated. Hence, the correct answer is 'Carbon - carbon double and triple bond'.

An acyclic compound is one that does not contain a ring structure. Methane (CHâ‚„) is a simple aliphatic compound with no cyclic structure, whereas Benzene, Pyrrole, and Cyclobutane are cyclic compounds.

An isopropyl group is a branched group with the structure -CH(CH₃)₂. 2-Methyl pentane contains one isopropyl group attached to the second carbon atom.