Join thousands of students who trust us to help them ace their exams!Watch the first video
Multiple Choice
Which of the following represents the balanced equation for the overall redox reaction between Fe³⁺(aq) and Cr(s) based on their standard reduction potentials?
A
3Fe³⁺(aq) + Cr(s) → 3Fe(s) + Cr³⁺(aq)
B
Fe(s) + Cr³⁺(aq) → Fe³⁺(aq) + Cr(s)
C
Fe³⁺(aq) + 3Cr(s) → 3Fe(s) + Cr³⁺(aq)
D
Fe³⁺(aq) + Cr(s) → Fe(s) + Cr³⁺(aq)
Verified step by step guidance
1
Identify the oxidation and reduction half-reactions. Fe³⁺(aq) is reduced to Fe(s), and Cr(s) is oxidized to Cr³⁺(aq).
Write the reduction half-reaction: Fe³⁺(aq) + 3e⁻ → Fe(s). This shows the gain of electrons by iron ions.
Write the oxidation half-reaction: Cr(s) → Cr³⁺(aq) + 3e⁻. This shows the loss of electrons by chromium.
Combine the half-reactions to form the overall redox reaction. Ensure that the electrons lost in the oxidation half-reaction equal the electrons gained in the reduction half-reaction.
Verify the balanced equation: Fe³⁺(aq) + Cr(s) → Fe(s) + Cr³⁺(aq). Check that the number of atoms and charges are balanced on both sides of the equation.