Question

[ Hg i4 ] 2- find the oxidation no.
​

Answer 1

Answer:

Nessler's Reagent is K2[HgI4] in alkaline medium like NaOH or KOH.

To find the oxidation number of Hg,let us first assume it's oxidation number to be x.Now,consider the compound as anion and cation-K+ and [HgI4]2-.

In the complex,[HgI4]2-,iodine has an oxidation state of -,the total sum of oxidation number of Hg and I should equal -2.

x-4=-2

Or x=-2+4=2

Thus,Mercury has an oxidation number of +2 in Nessler's Reagent.