wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

In the 'ring test' of NO3− ion, there is the formation of a brown color ring which has a formula:

A
[Fe(H2O)4NOSO4]2+
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
[Fe(H2O)5NO]2+
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
[Fe(H2O)5NO]SO4
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D
[Fe(H2O)4NO]3+
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is C [Fe(H2O)5NO]SO4
NO3 gives brown ring test
A common nitrate test, known as the brown ring test can be performed by adding iron(II) sulfate to a solution of a nitrate, then slowly adding concentrated sulfuric acid such that the sulfuric acid forms a layer above the aqueous solution. A brown ring will form at the junction of the two layers, indicating the presence of the nitrate ion. Note that the presence of nitrite ions will interfere with this test.
The overall reaction is the reduction of the nitrate ion by iron(II) which is oxidised to iron(III) and formation of a nitrosyl complex.
NO3+3Fe2++4H+3Fe3++NO+2H2O
[Fe(H2O)6]2++NO[Fe(H2O)5(NO)]2+ brown ring

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Introduction
CHEMISTRY
Watch in App
Join BYJU'S Learning Program
CrossIcon