Question

Which of the following reaction takes place at cathode in high temperature fuel cell using coal?

(a) \(\frac{1}{2}\) O2+ CO2+ 2e^–  →CO3^-2

(b) C+2CO3^-2  →3CO2+ 4e^–

(c) CO+CO3^-2  →2CO2+ 2e^–

(d) H2+ CO3^-2  →  H2 O+CO2+ 2e^–

I have been asked this question in an international level competition.

Query is from Inorganic Chemical topic in portion Inorganic Chemical Industries of Chemical Technology

Answer 1

Right answer is (a) \(\frac{1}{2}\) O2+ CO2+ 2e^–  →CO3^-2

Best explanation: \(\frac{1}{2}\) O2+ CO2+ 2e^–  →CO3^-2 being reduction reaction takes place at cathode. C+2CO3^-2  →3CO2+ 4e^– Is an anodic reaction for CH4, CO+CO3^-2  → 2CO2+ 2e^– is an anodic reaction for CO and H2+ CO3^-2 →  H2 O+CO2+ 2e^– is an anodic reaction for H2.