@ ValleyFiah- Cougars explained how soluble ionic compounds act in solution, but as far as your question goes, I can go into a little more detail. When you mix two ionic equations, sometimes they form insoluble ionic compounds as well as soluble ionic compounds.
An example would be a reaction between Manganese Nitrate and Sodium Hydroxide. When you mix these two solutions together, you get a solid (a precipitate) and another aqueous solution. Your products in the reaction are actually the brown solid manganese hydroxide mixed into a solution of sodium nitrate. The dissolved ions actually reform into different compounds, one of which happens to be insoluble.
This type of reaction can be used in the real world to separate chemical compounds from waste chemicals to create something that is economically valuable. Something like Manganese Hydroxide would be used to test oxygen content in fish tanks so it would have a value as an extracted precipitate.