Para aminophenylacetic acid and 4 aminoantipyrine can be added to the bath and in {HEAD ~ the presence} of sodium ferrocyanide reduce {TAIL ~ the rate} of oxidation of the bivalent tin ion 
Para aminophenylacetic acid and 4 aminoantipyrine can be added to the bath and in { HEAD ~ the presence } of sodium ferrocyanide reduce { TAIL ~ the rate } of oxidation of the bivalent tin ion
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 OTH OTH OTH OTH OTH OTH OTH