Question

in a particular redox reaction, Cr is oxidized to CrO42- and Ag+ is reduced to Ag. Complete and balance the equation for this reaction in acidic solution.

Answer 1

Cro42ag What is the percent for the fraction nine twentieths? 1. 9% 2. 20% 3. 45% 4. 90%

Answer 2

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:

$Cr+4H_2O+6Ag^++6e^-\rightarrow CrO_4^{2-}+8H^+6e^-+6Ag$

$Cr+4H_2O+6Ag^+\rightarrow CrO_4^{2-}+8H^++6Ag$