Answer
(b) and (c) will always be spectator ions.
Work Step by Step
a.) Chlorine will not always be a spectator ion. If it is bonded to silver, lead, or mercury, the solid is insoluble.
b.) Nitrate is always a spectator ion. See solubility rules.
c.) Ammonium is always a spectator ion. See solubility rules
e.) Sulfate salts are mostly soluble, but not when it is bonded to lead, calcium, mercury, or barium
