Q61P - Chemistry: Molecular Nature Of Matter And Change

Question

Use Figure 9.20, p. 364, to indicate the polarity of each bond with a polar arrow:

(a) N-B

(b) N-O

(c) C-S

(d) S-O

(e) N-H

(f) Cl-O

Step-by-Step Solution

Answer

Covalent bonds are typically referred to as "polar" or "nonpolar." To determine the polarity of a covalent bond numerically, compute the difference in electronegativity between the atoms; if the result is always between 0.4 and 1.7, the bond is polar covalent.

Step 1: Electronegativity and Polarity

As the absolute value of the electronegativity difference increases, so does the polarity of these bonds. The atom denoted by the δ– symbol is the more electronegative of the two.

Step 2: Polar arrow

Thus, the of each bond with a polar arrow is

(a) $\mathrm{N}\leftarrow \mathrm{B}$ 

(b) $N\to O$ 

(c) $C\leftarrow S$ 

(d) $S\to O$

(e) $\mathrm{N}\leftarrow \mathrm{H}$

(f) $\mathrm{CI}\to \mathrm{O}$