Question

At 300ºC, FeCl3 :

• A. Decomposes into FeCl2 and Cl2
• B. Decomposes into Fe and Cl2
• C. Sublimes to give liquid FeCl3
• D. Sublimes to give gaseous dimer (FeCl3)2

Answer 1

Answer: (D)

Sublimes to give gaseous dimer (FeCl3)2

Answer 2

HNO3 being strong oxidising agent oxidises iron to its oxides (Fe3O4) which forms a thin protective layer over the metal. This makes the iron passive.