Question 5.4: Predict which member of each of the following pairs of eleme......
Predict which member of each of the following pairs of elements has the greater electronegativity value based on periodic table electronegativity relationships.
a. Cl or Br b. C or O c. Li or K d. Al or N
a. Cl and Br are in the same periodic table group, with Cl being above Br. Therefore Cl is the more electronegative element, as electronegativity decreases going down a group.
b. C and O are in the same periodic table period, with O being farther to the right. Therefore O has the greater electronegativity, as electronegativity increases going across a period.
c. Li and K are in the same group, with Li being two positions above K. Therefore Li is the more electronegative element, as electronegativity decreases going down a group.
d. Al is in Period 3 and N is in Period 2. The element P can be used as a “link” between the two elements. It is in the same period as Al and the same group as N. The periodic table period trend predicts that P is more electronegative than Al and the periodic table group trend predicts that N is more electronegative than P. Therefore, N is more electronegative than Al.