`KBr+MnO_2+H_2SO_4 (conc.)toKHSO_4+MnSO_4+H_2O+[X]` (unbalanced equation)

Options

A. X turns starch paper orange red
B. X with `AgNO_3` solution gives a pale yellow ppt which is completely soluble in dilue ammonium hydroxide
C. X produces violet colour in organic layer in Kl solution
D. X is liberated when a mixture of KBr, `K_2Cr_2O_7` and conc. `H_2SO_4` is heated
`KBr+MnO_2+H_2SO_4to KHSO_4+MnSO_4+H_2O+[X]`

Answer

A,C,D

Explanation

`2KBr+MnO_2+3H_2SO_4 to 2KHSO_4 + MnSO_4 + 2H_2O + Br_2(X)`
(A)`Br_2`+starch`to` starch bromine adsorption complex (orange red)
(C )`2KI+Br_2 to 2KBr+I_2`(violet) soluble in organic layer.
(D)`K_2Cr_2O_7 +6KBr+7H_2SO_4 to 3Br_2 + Cr_2(SO_4)_3+4K_2SO_4 +7H_2O`
(B)AgBr ppt. (pale yellow) is only partially soluble in `NH_4OH`