Spectator Ions?

[Craig_Choi_2A]

I noticed in 6D.15 that chlorine is a spectator ion. I know that they have no effect on the reaction, but how do we identify other potential spectator ions or are they things that should just memorized?

[Lizzie Su 1I]

I definitely wouldn't memorize them because there could be reactions where chlorine isn't a spectator ion (for example). Once you have the full reaction and show that strong acids and bases are dissociated, you can cancel ions that appear on both sides of the reaction (and thus don't participate); these are your spectator ions.