There is no especial limitation on the iron compound if it is a compound containing an iron atom in {HEAD ~ its molecule} and is soluble in {TAIL ~ the aforementioned reaction liquid} 
There is no especial limitation on the iron compound if it is a compound containing an iron atom in { HEAD ~ its molecule } and is soluble in { TAIL ~ the aforementioned reaction liquid }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL