In the reaction sequence: `CrO_(2)Cl_(2)overset(NaOH) to A overset(dil. H_(2)SO_(4)) to B overset (NaOH) to C overset(AgNO_(3)) to D`
Identify `[A]` to `[D]`.

Answer

A=`Na_(2)CrO_(4)`, B=`Na_(2)Cr_(2)O_(7)` , C=`Na_(2)CrO_(4)` , D=`Ag_(2)CrO_(4)`

Explanation

`CrO_(2)Cl_(2)+4NaOH to Na_(2)CrO_(4) (A)+2NaCl + 2H_(2)O`
`Na_(2)CrO_(4)+H_(2)SO_(4) to 2Na_(2)Cr_(2)O_(7)(B)+Na_(2)SO_(4)+H_(2)O`
`Na_(2)Cr_(2)O_(7) +2Na_(2)CrO_(4) (C )+H_(2)O`
`Na_(2)CrO_(4) +2AgNO_(3) to Ag_(2)CrO_(4) (D) +2NaNO_(3)`