Answer:
B. Spectator ions
Explanation:
Spectator ions are described as spectators literally because they "spectate", or, in other words, do not participate in the overall reaction. They may show up in the reaction equation, but they don't react themselves.
Thus, spectator ions stay unchanged throughout a reaction. We see many spectator ions in precipitation reactions. Remember that ionic compounds disassociate in solution.
For example, the reaction between silver nitrate [tex]AgNO_{3}[/tex] and sodium chloride [tex]NaCl[/tex] produces a solid precipitate of silver chloride [tex]AgCl[/tex] as represented by the equation below:
[tex]Ag^+_{(aq)} + NO^-_{3(aq)}+Na^+_{(aq)}+Cl^-_{(aq)}[/tex] -------> [tex]AgCl_{(s)}+Na^+_{(aq)}+NO_{3(aq)}^-[/tex]
However, the sodium and nitrate ions remained aqueous, like before, so they did not react. Thus, they are spectator ions.
