Question

The prussian blue colour obtained during the
test of nitrogen by Lassaigne’s test is due to
the formation of
1) Fe4[Fe(CN)6]3
2) Na3[Fe(CN)6]
3) Fe(CN)3
4) All the above

Answer 1

Explanation:

Reaction takes place in Lassaigne's test are as :

Na+C+N⟶NaCN

6NaCN+FeSO

4

⟶Na

4

[Fe(CN)

6

]+Na

2

SO

4

Na

4

[Fe(CN)

6

]+Fe

+

3⟶Fe

4

(Fe(CN)

6

]

3

So, $$Fe_4(Fe(CN)_6]_3$$ is responsible for prussian blue colour obtained during the test of Nitrogen and Lassaigne test.

O−nitrophenal is more volatile than p−nitrophenal. There is intramolecular H− bonding in O− nitrophenal while in p− nitrophenal there is intermolecular hydrogen bonding which cause association of molecule.

Intermolecular H− bondingincrease, boiling point increases while volatility reduces