The melting points of dichlorobenzenes are: 1,2-isomer -17 degC, 1,3-isomer -25 degC, 1,4-isomer +53 degC. The high value for the 1,4-isomer is best explained by

its symmetrical shape, which packs better in the crystal lattice

its higher dipole moment than the other two isomers

its symmetrical shape, which packs better in the crystal lattice

its larger molecular mass than the 1,2- and 1,3- isomers

stronger hydrogen bonding between molecules

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The melting points of dichlorobenzenes are: 1,2-isomer $- 17^{\circ} C$ , 1,3-isomer $- 25^{\circ} C$ , 1,4-isomer $+ 53^{\circ} C$ . The high value for the 1,4-isomer is best explained by

Aits higher dipole moment than the other two isomers
Bits symmetrical shape, which packs better in the crystal lattice
Cits larger molecular mass than the 1,2- and 1,3- isomers
Dstronger hydrogen bonding between molecules

Answer: B

All three isomers have the same molar mass. The para isomer is the most symmetrical (zero dipole moment) and fits best into the crystal lattice, so more energy is needed to melt it. Its dipole moment is lower, not higher, and there is no hydrogen bonding.

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The melting points of dichlorobenzenes are: 1,2-isomer −17 ∘C, 1,3-isomer −25 ∘C, 1,4-isomer +53 ∘C. The high value for the 1,4-isomer is best explained by

Answer: B

More questions on Reactions of aryl halides

The melting points of dichlorobenzenes are: 1,2-isomer $- 17^{\circ} C$ , 1,3-isomer $- 25^{\circ} C$ , 1,4-isomer $+ 53^{\circ} C$ . The high value for the 1,4-isomer is best explained by