Pedant alert! "Salt doesn't just contain sodium and clorine, it is sodium and clorine (NaCl)."
Don's correct in that refined table salt is NaCl but a chemist would assert this means it contains sodium and chloride. If it contained chlorine we'd probably be very unhappy about it. Such terminology can get confusing; in earlier posts I mentioned iodine (in much the same way that Don mentioned chlorine), iodate (a commonly-used commercial term for added iodide, the counterpart of chloride) and iodised, the even more commonly used commercial term for a product (usually table salt or bread) where some digestible form of iodine (there I go again) has been added during processing.