The pair from the following pairs having both compounds with net non-zero dipole moment is
Solution
<p>The correct option from the pairs having both compounds with a net non-zero dipole moment is:</p>
<p><b>Option A</b>: $\text{cis-butene, trans-butene}$
cis-butene has a net dipole moment because the two alkyl groups are on the same side of the molecule, causing an imbalance in the distribution of electrons. However, trans-butene is symmetric, so the dipole moments of the two alkyl groups cancel each other out, giving it a net dipole moment of zero. Therefore, this pair does not have both compounds with a net non-zero dipole moment.</p>
<p><b>Option B</b>: $\text{CH}_2\text{Cl}_2, \text{CHCl}_3$
Both $\text{CH}_2\text{Cl}_2$ (dichloromethane) and $\text{CHCl}_3$ (chloroform) have a net non-zero dipole moment due to the difference in electronegativity between the hydrogen and chlorine atoms. Hence, this pair has both compounds with a net non-zero dipole moment.</p>
<p><b>Option C</b>: $\text{Benzene, Anisidine}$
Benzene has a symmetrical structure, leading to a net zero dipole moment. Anisidine, however, does have a net dipole moment due to the asymmetry in its structure. Therefore, this pair does not have both compounds with a net non-zero dipole moment.</p>
<p><b>Option D</b>: $\text{1,4-Dichlorobenzene, 1,3-Dichlorobenzene}$
$\text{1,4-Dichlorobenzene}$ has a symmetrical structure, leading to a net zero dipole moment. However, $\text{1,3-Dichlorobenzene}$ has a non-zero dipole moment due to the asymmetry in its structure. Therefore, this pair does not have both compounds with a net non-zero dipole moment.</p>
About this question
Subject: Chemistry · Chapter: Haloalkanes and Haloarenes · Topic: Nomenclature and Properties
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