A half-cell consisting of Cr₂O₇²⁻ ( 0.01 M) and Cr³⁺ ( 0.1 M) in an acidic solution has an electrode potential of 0.917 V. If the standard reduction potential of the dichromate half-cell is 1.33 V, what is the pH of the solution? (Nearest I

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A half-cell consisting of Cr₂O₇²⁻ ( 0.01 M) and Cr³⁺ ( 0.1 M) in an acidic solution has an electrode potential of 0.917 V. If the standard reduction potential of the dichromate half-cell is 1.33 V, what is the pH of the solution? (Nearest Integer) Given: 2.303RT F = 0.059 V

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Correct answer: 3

The balanced half-reaction for the reduction of dichromate in acidic medium is: Cr₂O₇²⁻ + 14H^+ + 6e^- 2Cr³⁺ + 7H₂O Here, the number of electrons transferred, n = 6 . Applying the Nernst equation: E = E^ - 0.059 n [Cr³⁺]^2 [Cr₂O₇²⁻][H^+]¹⁴ Substitute the given values: 0.917 = 1.33 - 0.059 6 (0.1)^2 (0.01)[H^+]¹⁴ 0.917 - 1.33 = - 0.059 6 0.01 0.01[H^+]¹⁴ -0.413 = - 0.059 6 ([H^+]⁻¹⁴) 0.413 6 0.059 = -14 [H^+] 42 = 14 pH pH = 42 14 = 3 Answer: 3

A half-cell consisting of Cr₂O₇²⁻ ( 0.01 M) and Cr³⁺ ( 0.1 M) in an acidic solution has an electrode potential of 0.917 V. If the standard reduction potential of the dichromate half-cell is 1.33 V, what is the pH of the solution? (Nearest Integer) Given: 2.303RT F = 0.059 V

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