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कर्नाटक बोर्ड पी.यू.सी.पीयूसी विज्ञान 2nd PUC Class 12

EcellΘ for some half cell reactions are given below. On the basis of these mark the correct answer. - Chemistry

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प्रश्न

`E_(cell)^Θ` for some half cell reactions are given below. On the basis of these mark the correct answer.

(a) \[\ce{H^{+} (aq) + e^{-} -> 1/2 H_2 (g); E^Θ_{cell} = 0.00V}\]

(b) \[\ce{2H2O (1) -> O2 (g) + 4H^{+} (aq) + 4e^{-}; E^Θ_{cell} = 1.23V}\]

(c) \[\ce{2SO^{2-}_{4} (aq) -> S2O^{2-}_{8} (aq) + 2e^{-}; E^Θ_{cell} = 1.96V}\]

(i) In dilute sulphuric acid solution, hydrogen will be reduced at cathode.

(ii) In concentrated sulphuric acid solution, water will be oxidised at anode.

(iii) In dilute sulphuric acid solution, water will be oxidised at anode.

(iv) In dilute sulphuric acid solution, \[\ce{SO4^{2-}}\] ion will be oxidised to tetrathionate ion at anode.

टीपा लिहा
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उत्तर

(i) In dilute sulphuric acid solution, hydrogen will be reduced at cathode.

(iii) In dilute sulphuric acid solution, water will be oxidised at anode.

Explanation:

In dilute sulphuric acid solution, hydrogen will be reduced at cathode.

\[\ce{H^{+} + e^{-} -> 1/2 H2}\]

And \[\ce{H2O}\] is oxidized at node.

\[\ce{2H2O -> O2 + 4H^{+} + 4e^{-}}\]

While in concentrated solution of sulphuric acid, SO-2 ions are oxidized to tetrathionate (SO2) ions.

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पाठ 3: Electrochemistry - Exercises [पृष्ठ ३६]

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एनसीईआरटी एक्झांप्लर Chemistry [English] Class 12
पाठ 3 Electrochemistry
Exercises | Q II. 19. | पृष्ठ ३६

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