(A) In acidic solution, dichromate ion oxidizes oxalic acid, H₂C₂O₄(aq), to CO₂(g) in a reaction with E°_cell = 1.81 V.

Use the value of E°_cell for this reaction, together with appropriate data from Table 19.1, to determine E° for the CO₂(g)/H₂C₂O₄(aq) electrode.

Table 19.1

(B) In an acidic solution, O₂(g) oxidizes Cr²⁺(aq) to Cr³⁺(aq). The O₂(g) is reduced to H₂O(l). E°_cell for the reaction is 1.653 V. What is the standard electrode potential for the couple Cr³⁺/Cr²⁺?

Transcribed Image Text:

Cr₂O₂ (aq) + 3 + 3 H₂C₂O4(aq) H₂C₂O4(aq) + 8 H+ (aq) 2 Cr³+ (aq) + 7 H₂O + 6 CO₂(g)