NO3-

Question 1

i)NO3- + conc.H2SO4—->
ii)NO3- + Zn/Al + NaOH—->
iii)All NO3- are water soluble

Answer 1

i)NO3- + conc.H2SO4—->NO2 + O2
ii)NO3- + Zn/Al + NaOH—->NH3 + Na2ZnO2/Na2AlO2 + H2O
iii)All NO3- are water soluble

Question 2

Brown Ring Test for NO3-:

Answer 2

NO3- + conc.H2SO4 +FeSO4—->HNO3 + Fe+2—->Fe+3 + NO—FeSO4—->[Fe(H2O)5NO]SO4

Question 3

precautions for brown ring test

Answer 3

i)do not shake
[Fe(H2O)5NO]SO4—shake—->NO
ii)test tube should be free from Ba+2,Sr+2,Pb+2,Hg+2 because their sulfates are water insoluble
iii)Br-,I- also gives brown solution with conc.H2SO4 of Br2,I3- so conc. H2SO4 is not thoroughly mixed in test tube
iv)NO2- can also perform brown ring test
to perform test of NO3- containing NO2-,N(-3) groups are mixed