{TAIL ~ Para aminoacetanilide} and para nitroacetanilide can also be used in {HEAD ~ the presence} of sodium ferrocyanide 
{ TAIL ~ Para aminoacetanilide } and para nitroacetanilide can also be used in { HEAD ~ the presence } of sodium ferrocyanide
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH