Question

नमक के जलीय विलयन के विद्युत् अपघटन में कौन-सी अर्धसेल अभिक्रिया ऐनोड पर होगी?

विकल्प

• \[\ce{Na+ (aq) + e^- -> Na (s);  E^⊖_{cell}}\] = - 2.71 V

• \[\ce{2H2O (l) -> O2(g) + 4H+ (aq) + 4e^- ; E^⊖_{cell} = 1.23V}\]

• \[\ce{H^+ (aq) + e^- -> 1/2 H2 (g); E^⊖_{cell} = 0.00V}\]

• \[\ce{Cl^- (aq) -> 1/2 Cl2 (g) + e^- ; E^⊖_{cell} = 1.36V}\]

Answer 1

\[\ce{Cl^- (aq) -> 1/2 Cl2 (g) + e^- ; E^⊖_{cell} = 1.36V}\]

स्पष्टीकरण -

जलीय के इलेक्ट्रोलिसिस के दौरान

\[\ce{NaCl -> Na^+ + Cl^-}\]

\[\ce{H2O -> H+ + OH-}\]

\[\ce{Na+ + e- -> Na (E^{⊖}_{cell} = - 2.71V)}\]

\[\ce{H^+ e- -> 1/2 H2 E^{⊖}_{cell} = 0.00V}\]

At cathode,

\[\ce{H2O + e- -> 1/2 H2 + OH-}\]

At anode, two reactions are possible.

\[\ce{Cl^{-} -> 1/2 Cl2 + e- ; E^{⊖}_{cell} = 1.36V}\]

\[\ce{2H2O -> O2 + 4H+ + 4e- ; E^{⊖}_{cell} = 1.23V}\]