Find the number of reaction (s) in which no redox change takes place:
(a). `BaCl_(2)+Na_(2)CrO_(4)overset(CH_(3)COOH)to`
(b). `K_(2)Cr_(2)O_(7)+NaOHto`
(c). `Cr_(2)O_(7)^(2-)+NO_(3)^(-)overset(H^(+))to`
(d). `Cr_(2)O_(7)^(2-)+C_(2)H_(5)Ohoverset(H^(+))to`

Answer

3

Explanation

(a). `BaCl_(2)+Na_(2)CrO_(4)overset(CH_(3)COOH)toBaCrO_(4)darr+2NaCl`
(b). `K_(2)Cr_(2)O_(7)+NaOHtoK_(2)CrO_(4)`
`CrO_(4)^(2-)underset(OH^(-))overset(H^(+))hArrCr_(2)O_(7)^(2-)`
(c). `Cr_(2)O_(7)^(2-)+NO_(3)^(-)overset(H^(+))to`no reaction.
(d). `Cr_(2)O_(7)^(2-)+C_(2)H_(5)OH overset(H^(+))toCH_(3)-COOH+Cr^(+3)`.