Which of the following statement is INCORRECT?

Mixture of  CO3−2  and HCO3− can be distinguished by phenolphthalein, which gives pink colour with HCO3− ions

Mixture of NO2− and NO3− can be distinguished by ‘ring-test’ NO3− ions gives brown ring while  NO2− ions gives a green coloured solution

Mixture of Br− and NO3- ions can be distinguished by adding  H2SO4 and passing the reddish brown gas evolved through FeSO4 solution. If it turns black, it is NO3- and if it does not turn black it is Br− ion.

Chromyl chloride test fails with Br- and I- ions since both chromyl bromide and chromyl iodine are non volatile in nature.