Question

Explain in terms of electronegativity whether the bonds in CHIFBr (above) are polar or not.

Answer 1

This is non polar because the elements are relatively close on the periodic table

Answer 2

A bond between two atoms is considered to be polar, if the electronegativity difference between the atoms bonded is greater than 0.4

The electro-negativity values of C, H, F, Br and I are,

C = 2.55, H = 2.20, F = 3.98, Br = 2.96, I = 2.66

The electronegativity difference between C and H bond = 2.55 - 2.20 = 0.35

The electronegativity difference between C and F bond = 3.98-2.55 = 1.43

The electronegativity difference between C and Br bond = 2.96 - 2.55 = 0.41

The electronegativity difference between C and I bond = 2.66 - 2.55= 0.11

All the bonds have electro-negativity difference less than or equal to 0.4 except C-Br and C - F bond. So, the C-Br and C-F bond will be polar, and all the other bonds will be non-polar.