In aqueous solutions, soluble salts will dissociate into
ions. Since all salts of nitrates are completely soluble in water, AgNO3 and
KNO3 will dissociate into Ag+, K+, and NO3- ions. KBr is also soluble in water,
forming K+, Br- ions.
Rewriting the equation:
Ag+ + NO3- + K+ NO3- -> K+ + NO3- + AgBr(s)
Spectator ions are those that does not participate in the
reaction, which means they are found in both sides in the equation above. K+
and NO3- are those ions.
