Question #65e0b

1 Answer
Aug 2, 2017

Do you have a potassium salt?.........I presume you do.

Explanation:

#K_2[Fe(C-=N)_6]#, #"potassium ferrocyanide"#, #K_3[Fe(C-=N)_6]#, #"potassium ferricyanide"#, are the typical #stackrel(+III)"Fe"# and #stackrel(+II)"Fe"# salts. How to assign these numbers? Look at the formulae of the salts, we got #3xxK^+ +Fe^(3+) + 6xx""^(-):C-=N#, to give a NEUTRAL ferric salt; else #2xxK^+ +Fe^(2+) + 6xx""^(-):C-=N# to give the ferrous salt.

As an inert gas krypton forms a couple of oxides, and fluorides, but I don't think it has been coordinated to an iron centre.