Answer:
The complete and balance the equation for this reaction in acidic solution is given by:
\(Cr+4H_2O+6Ag^+\rightarrow CrO_4^{2-}+8H^++6Ag\)
Explanation:
Oxidation reaction of chromium to chromate in acidic medium:
\(Cr\rightarrow CrO_4^{2-}\)
Add 4 molecules of water on the left hand side to balance the oxygen:
\(Cr+4H_2O\rightarrow CrO_4^{2-}\)
Now balance hydrogen atoms by adding hydrogen ions on opposite to the side where water molecule are present .
\(Cr+4H_2O\rightarrow CrO_4^{2-}+8H^+6e^-\)....[1]
In last, to balance the charge on the both sides add electrons to sides where positive charge is more.
Reduction reaction of silver ions to silver in acidic medium:
\(Ag^++e^-\rightarrow Ag\)..[2]
By [1] + 6 × [2] , we will get the balance equation for this reaction in acidic solution:
\(Cr+4H_2O+6Ag^++6e^-\rightarrow CrO_4^{2-}+8H^+6e^-+6Ag\)
\(Cr+4H_2O+6Ag^+\rightarrow CrO_4^{2-}+8H^++6Ag\)
