Grade 11Physical Chemistry

ferric iodide is very unstable but ferric chloride is stable.why?

kiran kumar

12 Years agoGrade 11

3 Answers

Sunil Kumar FP

11 Years ago

ferric iodide is very unstable but ferric chloride is stable:-
I- is a stronger reducing agent in comparison to Cl-Fe+3 is easily reduced by iodide ion.Therefore it gets reduced to iodine.The standard electrode potential of chlorine is much higher,it means it is a better oxiding agent.Also the large size of iodine makes it a strong reducing agent
FeI3 ------->FeI +I2

Sapna Jha

10 Years ago

FeI3 is unstable because Fe^+3 is strong oxidising agent but I^- has very less reducing power. (chemistryclass.org)

Parag Dasgupta

9 Years ago

I- ion is stronger reducing agent than Cl- ion.Hence Fe3+ ion is easily reduced by I- ion to Fe2+ ion & itself gets oxidized to I2.But this doesn`t happen in case of FeCl3.Hence FeCl3 is stable but FeI3 is unstable.2Fe3+ +2I- ->2Fe2+ +I2.