All nitrates and all sodium salts are soluble. This means a given precipitate XY can be produced by mixing together solutions of:
For example, to prepare a precipitate of calcium carbonate:
calcium nitrate + sodium carbonate → sodium nitrate + calcium carbonate
Ca(NO3)2(aq) + Na2CO3(aq) → 2NaNO3(aq) + CaCO3(s)
It also works if potassium carbonate solution or ammonium carbonate solution is used instead of sodium carbonate solution. Remember that all common potassium and ammonium salts are soluble.
Name two suitable solutions that, when mixed together, will produce a precipitate of silver chloride.
Silver nitrate solution and sodium chloride solution (or potassium chloride solution, or ammonium chloride solution).
This is an outline method for making a pure, dry sample of an insoluble salt.