Related Problems with Solution

Problem 1 : Balance the following redox equation occurring in acidic solution:

[Cr2O72+HNO2Cr3++NO3.]

Solution :

To balance this equation, follow these steps:

Step 1: Assign oxidation states to each element: [Cr2O72:Cr6+,O2] [HNO2:H1+,N3+,O2] [Cr3+:Cr3+] [NO3:N5+,O2]

Step 2: Write down the unbalanced equation: [Cr2O72+HNO2Cr3++NO3.]

Step 3: Break the reaction into half-reactions for oxidation and reduction: [Oxidation:HNO2NO3] [Reduction:Cr2O72Cr3+]

Step 4: Balance each half-reaction: Oxidation: [HNO2NO3] Add 3 electrons (e⁻) to the left side to balance the charge.

Reduction: [Cr2O72Cr3+] Add 6 electrons (e⁻) to the right side to balance the charge.

Step 5: Multiply the half-reactions by coefficients to balance the number of electrons: [6(HNO2NO3)] [3(Cr2O72Cr3+)]

Step 6: Add the balanced half-reactions to get the overall balanced equation: [6HNO2+3Cr2O726NO3+3Cr3+.]