41. The best known is probably a process using ammonium ferric citrate and potassium ferricyanide. 42. The teeth are coated with magnetite, a hard ferric / ferrous oxide mineral. 43. The ferric cations produced can also oxidize additional pyrite and reduce into ferrous ions: 44. These two pigments are chromium oxide greens / ferric ferrocyanide, or Prussian blue. 45. Finally, arsenic oxide is removed when the gas is exposed to ferric hydroxide. 46. Treatment with more iron metal converted the ferric bromide to ferrous bromide via comproportionation. 47. This enzyme is also called "'ferric leghemoglobin reductase " '. 48. It reacts with ferric salts to form a deep-red ferric thiocyanate complex: 49. It reacts with ferric salts to form a deep-red ferric thiocyanate complex: 50. For example, ferric chloride can be prepared thus, but ferrous chloride cannot.
