Question

the image shows a periodic table with the principle groups, and shows the electronegativities of each atom. this is useful when determining the polarity of a substance. which of the following bonds is classified as a polar bond?

Explanation:

Step1: Recall polarity - bond rule

A polar bond has an electronegativity difference ($\Delta \chi$) between 0.5 - 1.9.

Step2: Find electronegativities from table

For Si - F: Electronegativity of Si = 1.8, F = 4.0. $\Delta \chi=4.0 - 1.8=2.2$.
For K - Cl: Electronegativity of K = 0.8, Cl = 3.0. $\Delta \chi=3.0 - 0.8 = 2.2$.
For S - O: Electronegativity of S = 2.5, O = 3.5. $\Delta \chi=3.5 - 2.5=1.0$.
For Br - Br: Electronegativity of Br = 2.8, $\Delta \chi=2.8 - 2.8 = 0$.

Step3: Determine polar bond

Since the electronegativity difference for S - O is 1.0 which is in the range 0.5 - 1.9, S - O is a polar bond.

Answer:

S - O