The incorrect statement is :
salts give red coloured borax bead test in reducing flame.
and ions give black precipitate with H2S in presence of HCl solution.
Ferric ion gives blood red colour with potassium thiocyanate.
ion gives chocolate coloured precipitate with potassium ferrocyanide solution.
As we have learned
Solubility product constant -
- wherein
For a pure solid substance the concentration remain constant
c
Due to common ion effect , sufficient and concentration not produce and not formed precipitate of NiS
Option 1)
salts give red coloured borax bead test in reducing flame.
This is incorrect
Option 2)
and ions give black precipitate with H2S in presence of HCl solution.
This is correct
Option 3)
Ferric ion gives blood red colour with potassium thiocyanate.
This is incorrect
Option 4)
ion gives chocolate coloured precipitate with potassium ferrocyanide solution.
This is incorrect
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