Selected Pauling electronegativity values are provided below for the second and third…
CHEMISTRY · Multi-part · AP · Chemistry · Atomic Structure and Properties · Atomic Structure and Properties
Problem
Selected Pauling electronegativity values are provided below for the second and third periods.
Group (left→right)
Li (1)
Be (2)
B (13)
C (14)
N (15)
O (16)
F (17)
Period 2
1.0
1.5
2.0
2.5
3.0
3.5
4.0
Period 3
0.9
1.2
1.6
2.0
2.4
3.0
4.0
Answer the following questions regarding the periodic behavior illustrated by these data.
(a) On the same qualitative set of axes, sketch normalized electronegativity (each period scaled so its maximum equals 1) versus group number for both periods. Comment on any differences in curvature between the two normalized plots.
(b) Derive a qualitative relationship connecting electronegativity to effective nuclear charge Zeff for main-group elements, citing evidence from the data.
(c) Using the relationship from part (b), assess whether the differences in electronegativity between homologous elements of Periods 2 and 3 are consistent with differences in average atomic radius. Provide a reasoned argument.
(d) Discuss one limitation of extending the electronegativity trend derived in parts (b) and (c) to first-row transition-metal elements. Include at least one electronic-structure–based consideration.