A test tube containing a nitrate and another containing a bromide and `MnO_(2)` are treated with concentrated `H_(2)SO_(4)`.The reddish brown fumes ev

Monjur Alahi

A test tube containing a nitrate and another containing a bromide and `MnO_(2)` are treated with concentrated `H_(2)SO_(4)`.The reddish brown fumes evolved are passed through water.The water will be coloured by :
A. the nitrate
B. the bromide
C. both
D. none of the two


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Salim Ahmed Kawsar

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Correct Answer - B
`NO_(3)^(-)` gives `NO_(2)` with concentrated `H_(2)SO_(4)` which on passing through water form colourless `HNO_(3)(l)` and `HNO_(2)(l)`
`Br^(-)+MnO_(2)` on heating with concentrated `H_(2)SO_(4)` gives `Br_(2)` gas which on passing through water imparts it a reddish brown colour.

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