Page 112 - Chemistry eBook

Ionic Bonds and Electronegativity
We can figure out whether the bond is ionic by finding the difference of the two atom’s electronegativities.
1. Subtract the electronegativity of one atom from the electronegativity of the other. 2. If the difference is 1.7 or more, the bond is ionic.
If the difference is less than 1.7, the bond is NOT ionic.
Do Li and F form an ionic bond?
a. Find the electronegativities of Li and F
by looking at Reffy, Table S (pp. 10-11). Li: 1
F: 4.
b. 4 – 1 = 3
Since 3 is more than 1.7, we know that this bond is ionic.
The greater the difference in electronegativity, the more stable/stronger the bond is.
There are many Regents questions on this topic.
If you are asked to find the electronegativity difference of an element with a subscript, ignore the subscript.
NO2: ignore the subscript 2.
112 © UNIT 4: BONDING