Question #966b5

1 Answer
Kaisha
May 15, 2017

See below.

Explanation:

Test for #Cr^(3+)# is treating it with NaOH. It gives a grey-green precipitate which is soluble in excess NaOH to give a dark green solution.

Or you can treat it with aqueous #NH_3# where it forms a grey-green precipitate and insoluble in excess ammonia.

It dissolves in dilute HCl to form solutions containing #Cr^(2+)#. So it would be 3.

Related questions
See all questions in Reactions Between Ions in Solutions
Impact of this question
2460 views around the world
You can reuse this answer
Creative Commons License