This answer is not quite correct. No reaction would occur if all the ions stayed in the solution and although one might think that all ionic compounds should be soluble, this is not the case. Certain ionic compounds are insoluble in water and thus would precipitate out of solution. If this happened, the reaction would be driven to completion. If two solutions of soluble ionic compounds such as silver nitrate and sodium chloride were mixed, a precipitate of silver chloride would form since silver chloride is insoluble in water. The sodium ions and the nitrate ions would stay in solution as "spectator ions". Is there any other way that this type of reaction could occur?