Question

Polarity of a bond depends on the difference in the electronegativity of the bonded atoms. The higher the difference in the electronegativity, the higher will be the polarity of the bond.

The boiling point of $ICl$ is about ${40}^{\circ }C$ higher than $B{r}_2$. This might be because :

• A. $I-Cl$ bond is stronger than $Br-Br$ bond
• B. $I.E.$ of $I<I.E.$ of $Br$
• C. $I-Cl$ is polar whereas $B{r}_2$ is non-polar
• D. the size of $I>Br$

Answer 1

Answer: (C)

$I-Cl$ is polar whereas $B{r}_2$ is non-polar

Compounds with high polarity usually have a higher boiling point than compounds with low polarity because the intermolecular forces are stronger in compounds with high polarity.

So, it takes more energy for the molecules to break away from these intermolecular forces. Here, $I$ and $Cl$ have different electronegativity making $ICl$ polar whereas bromine is non-polar.

Hence, the correct option is C.