The oxidation number is changed in which of the following case

(A) SO2 gas is passed into Cr2O72-/H+

(B) Aqueous solution of CrO42- is acidified

(C) CrO2Cl2 is dissolved in NaOH

(D)Cr2O72- solution is made alkaline

Concept Videos :-

#7 | Reactions of KMNO4 & K2Cr2O7: I
#8 | Reactions of KMNO4 & K2Cr2O7: II

Concept Questions :-

Chemistry of KMnO4, K2Cr2O7 & CrO5 and others

(A) Cr2O72- +SO2 +2H+2Cr3++3SO42- +H2O (change)        +6             +4                    +3         +6(B)2Cr2O42- + 2H+Cr2O72- +H2O ( No change)        +6                            +6(C)CrO2Cl2+2NaOHNaCrO4 (No change)       +6                                    +6(D)  Cr2O72- +2OH-2CrO42- +H2O ( No change)       +6                               +6

Difficulty Level:

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