The balanced oxidation-reduction reaction in basic solution is:
6 ClO⁻(aq) + 2 Cr(OH)₃(s) ⇒ 3 Cl₂(g) + 2 OH⁻(aq) + 2 CrO₄²⁻(aq) + 2 H₂O(l)
What is an oxidation-reduction reaction?
An oxidation-reduction (redox) reaction is a type of chemical reaction that involves a transfer of electrons between two species.
Let's consider the following unbalanced redox reaction.
Cr(OH)₃(s) + ClO⁻(aq) ⇒ CrO₄²⁻(aq) + Cl₂(g)
We will balance it using the ion-electron method.
- Step 1. Identify both half-reactions.
Reduction: ClO⁻(aq) ⇒ Cl₂(g)
Oxidation: Cr(OH)₃(s) ⇒ CrO₄²⁻(aq)
- Step 2. Perform the mass balance by adding H₂O and OH⁻ where necessary.
2 H₂O(l) + 2 ClO⁻(aq) ⇒ Cl₂(g) + 4 OH⁻(aq)
5 OH⁻(aq) + Cr(OH)₃(s) ⇒ CrO₄²⁻(aq) + 4 H₂O(l)
- Step 3. Perform the charge balance adding electrons where necessary.
2 H₂O(l) + 2 ClO⁻(aq) + 2 e- ⇒ Cl₂(g) + 4 OH⁻(aq)
5 OH⁻(aq) + Cr(OH)₃(s) ⇒ CrO₄²⁻(aq) + 4 H₂O(l) + 3 e-
- Step 4. Multiply both half-reactions by numbers that make the number of electrons gained and lost to be the same. Then, add them.
3 . (2 H₂O(l) + 2 ClO⁻(aq) + 2 e- ⇒ Cl₂(g) + 4 OH⁻(aq))
2 . (5 OH⁻(aq) + Cr(OH)₃(s) ⇒ CrO₄²⁻(aq) + 4 H₂O(l) + 3 e-)
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6 H₂O(l) + 6 ClO⁻(aq) + 6 e- + 10 OH⁻(aq) + 2 Cr(OH)₃(s) ⇒ 3 Cl₂(g) + 12 OH⁻(aq) + 2 CrO₄²⁻(aq) + 8 H₂O(l) + 6 e-
6 ClO⁻(aq) + 2 Cr(OH)₃(s) ⇒ 3 Cl₂(g) + 2 OH⁻(aq) + 2 CrO₄²⁻(aq) + 2 H₂O(l)
The balanced oxidation-reduction reaction in basic solution is:
6 ClO⁻(aq) + 2 Cr(OH)₃(s) ⇒ 3 Cl₂(g) + 2 OH⁻(aq) + 2 CrO₄²⁻(aq) + 2 H₂O(l)
Learn more about redox reactions here: https://brainly.com/question/26263317
