text: In the laboratory however , copper ( I ) iodide is prepared by simply mixing an aqueous solution of sodium or potassium iodide and a soluble copper ( II ) salt such copper sulfate .
simplified: Another way would be to react copper ( II ) sulfate and potassium iodide . This makes copper ( II ) iodide which as said before breaks down right away to make iodine and copper ( I ) iodide .