if a reaction involving iodide ions converting to iodine is first order with respect to iodide will this be true in reverse if one were to say the reaction is first order with respect to iodine?(this doubt arouse when i had to sketch out a concentration-time graph for such a reaction but it was the concntration of iodine i had to work with and i did sketch a curve but then was confused why i did so and may be it was because i thought order with respect to iodide is same as wrt iodine)