A researcher is comparing the electronegativity behavior of main-group elements with…
CHEMISTRY · Multi-part · AP · Chemistry · Atomic Structure and Properties · Atomic Structure and Properties
Problem
A researcher is comparing the electronegativity behavior of main-group elements with that of selected transition metals. Partial data are provided in the table.
Element
Atomic Number
Electronegativity (Pauling)
Ga
31
1.81
Ge
32
2.01
Zn
30
1.65
Cu
29
1.90
As
33
2.18
Use these data, together with periodic-trend reasoning, to answer the questions below.
(a) Using the elements in the table, rank Zn, Ga, and Ge from lowest to highest electronegativity. Justify your ranking with specific reference to periodic position and electronic configuration.
(b) Zinc’s electronegativity is lower than that of both Ga and Ge, even though Zn is to the left of both Ga and Ge only in the first row of the transition block. Provide a detailed explanation that accounts for (i) the effect of filled 3d subshells on shielding and (ii) the resulting effective nuclear charge experienced by the 4s and 4p electrons.
(c) Predict whether the bond between Zn and As in ZnAs₂ would be expected to possess greater or lesser ionic character than the bond between Ga and As in GaAs. Support your prediction with quantitative or qualitative arguments based on electronegativity differences.