Chemistry - GOC Question with Solution | TestHub
Match the compounds in List-I with the properties in List-II. A property in List-II may match more than one compound in List-I.
List-I (Compound) | List-II (Property) |
|---|---|
(P) | (1) Aromatic |
(Q) | (2) Anti-aromatic |
(R) | (3) Non-planar |
(S) | (4) Zero dipole moment |
Choose the option with the correct matching:
Options:
Answer:
Solution:
(P) The cyclopropenyl cation is planar, cyclic and conjugated with 2 π electrons: aromatic (1). Its shape is an equilateral triangle, so the dipole moment is zero (4).
(Q) Cyclobutadiene is planar, cyclic and conjugated with 4 π electrons: anti-aromatic (2). The rectangular molecule has zero dipole moment (4).
(R) Cyclooctatetraene avoids anti-aromaticity by adopting a tub shape: it is non-planar (3) and non-aromatic. The tub has symmetry, so the dipole moment is zero (4).
(S) Azulene has 10 π electrons in a planar bicyclic ring: aromatic (1). The five-membered ring is electron-rich and the seven-membered ring electron-poor, so it has a dipole moment (about 1 D). Not (4).
Correct matching: P 1,4; Q 2,4; R 3,4; S 1. Answer: (D).
