Which of the following statement(s) is/are correct with respect to bromide ions ?

Options

A. KBr on heating with `MnO_(2)` and concentrated `H_(2)SO_(4)` liberates `Br_(2) " and" SO_(2)` gases.
B. KBr on heating with concentrated `H_(2)SO_(4)` liberates `Br_(2) " and" SO_(2)` gases.
C. KBr forms HBr with concentrated `H_(3)PO_(4)`.
D. KBr(s) liberates `Br_(2)` on gentle warming with concentrated `H_(2)SO_(4)` and `K_(2)Cr_(2)O_(7)`(s).

Answer

B, C, D

Explanation

`(A) 2KBr+MnO_(2)+2H_(2)SO_(4) to Br_(2) uarr +2K^(+)+Mn^(2+)+2SO_(4)^(2-)+2H_(2)O`
(B) `2KBr+2H_(2)SO_(4) to Br_(2) uarr+SO_(2) uarr +SO_(4)^(2-)+2K^(+)+2H_(2)O`
(C ) `KBr+H_(3)PO_(4) to HBr +H_(2)PO_(4^(-))+K^(+)`
(D) `6KBr+K_(2)Cr_(2)O_(7)+7H_(2)SO_(4)to 3Br_(2)+2Cr^(3+)+2K^(+)+7SO_(4)^(2-)+7H_(2)O`