E - 172
#
 :
  (IRON OXIDES)
(i)   (+2, +3), 
(Iron oxide, black)
(ii)   (+3), 
(Iron oxide, red)
(iii)   (+3), 
(Iron oxide, yellow)
#
   :

#
  :

#
  :

#
 ,  :
#
  :
   .
   .
  .
#
###
