What does sodium bromide and potassium chloride yield?

a mixture of sodium, potassium, bromide, and chloride ions.

NaBr \, \rightleftharpoons \, Na^+ + Br^-

KCl \, \rightleftharpoons \, K^+ + Cl^-

Na^+ + Cl^- \, \rightleftharpoons \, NaCl

K^+ + Br^- \, \rightleftharpoons \, KBr



If you dissolved all of this in water, and let it dry out, you would have a mixture of all four possible salts:

KCl, \,\, NaCl, \,\, KBr, \,\, NaBr