Question

Balance the following redox reaction which takes place in an acidic solution using the half reaction method:

[Cr₂O₇²⁻(aq) + Ag(s) → Ag⁺(aq) + Cr⁺³(aq)]
a) (Cr₂O₇²⁻(aq) + 6Ag(s) → 14Ag⁺(aq) + 2Cr⁺³(aq))
b) (2Cr₂O₇²⁻(aq) + 14Ag(s) → 7Ag⁺(aq) + 4Cr⁺³(aq))
c) (Cr₂O₇²⁻(aq) + 14Ag(s) → 2Ag⁺(aq) + 2Cr⁺³(aq))
d) (2Cr₂O₇²⁻(aq) + 12Ag(s) → 6Ag⁺(aq) + 4Cr⁺³(aq))

Answer 1

To balance the given redox reaction in an acidic solution, use the half-reaction method following the outlined steps.

Step-by-step explanation:

To balance the given redox reaction in an acidic solution using the half-reaction method, we follow the steps below:

1. Balance each half-reaction for all elements except H and O.
2. Balance each half-reaction for O by adding H2O.
3. Balance each half-reaction for H by adding H+.
4. Balance each half-reaction for charge by adding electrons.
5. Combine the balanced half-reactions and cancel out the electrons.
6. Multiply the half-reactions, if necessary, to ensure the number of electrons cancels out.
7. Check that the atoms and charges are balanced.

Applying these steps, we can see that the correct balanced equation is option b) (2Cr₂O₇²⁻(aq) + 14Ag(s) → 7Ag⁺(aq) + 4Cr⁺³(aq)).