37 . Which of the elements below is most likely to form compounds in which it has an
incomplete octet?
(A) B
(B) C
(C) N
(D) O
(E) F
38 . Which element is most likely represented by X in the oxygen-containing ion, XO 4 3−?
(A) C
(B) N
(C) P
(D) S
(E) Cl
39 . Quartz, SiO 2 , has a high melting point and is insoluble in most solvents. Which type of
force best accounts for the physical properties of quartz?
(A) Hydrogen bonding
(B) Covalent bonding
(C) Ionic bonding
(D) P bonding
(E) Dispersion forces
40 . Which of the following atoms would have the largest ionic radii?
(A) F−
(B) O−2
(C) Na+
(D) Mg+2
(E) Al+3