Questions 19–23
17 . Commonly forms ionic compounds as a −1 anion
18 . Has the highest ionization energy of the elements listed
(A) Ag+ (aq) + Cl− → AgCl(s)
(B) C 5 H 12 (s) + 8 O 2 (g) → 5 CO 2 (g) + 6 H 2 O (l)
(C) NH 3 (s) + H 2 O (s) NH 4 + (s) + OH− (s)
(D) HC 2 H 3 O 2 (l) + OH− (aq) → H 2 O (l) + C 2 H 3 O 2 −(aq)
(E) CaCO 3 (s) → CaO (s) + CaO 2 (g)
19 . Most likely to proceed with a decrease in entropy
20 . The most exothermic of the reactions written
21 . An acid-base neutralization reaction
22 . A precipitation reaction
23 . A decomposition reaction