Advertisements
Advertisements
Question
In \[\ce{H2 - O2}\] fuel cell the reaction occurs at cathode is:
Options
\[\ce{O2_{(g)} + 2H2O_{(l)} + 4e^- -> 4OH^-_{( aq)}}\]
\[\ce{H^+_{( aq)} + OH^-_{( aq)} -> H2O_{(l)}}\]
\[\ce{2H2_{(g)} + O2_{(g)} -> 2H2O_{(g)}}\]
\[\ce{H^+ + e^- -> 1/2H2}\]
Advertisements
Solution
\[\ce{O2_{(g)} + 2H2O_{(l)} + 4e^- -> 4OH^-_{( aq)}}\]
APPEARS IN
RELATED QUESTIONS
Consider the following half cell reactions:
\[\ce{Mn^{2+} + 2e^- -> Mn}\] E0 = –1.18 V
\[\ce{Mn^{2+} -> Mn^{2+} + e^-}\] E0 = –1.51 V
The E0 for the reaction \[\ce{3Mn^{2+} -> Mn + 2Mn^{3+}}\], and the possibility of the forward reaction are respectively.
The button cell used in watches functions as follows.
\[\ce{Zn_{(s)} + Ag2O_{(s)} + H2O_{(l)} ⇌ 2Ag_{(s)} + Zn^{2+}_{( aq)} + 2OH^-_{( aq)}}\] the half cell potentials are \[\ce{Ag2O_{(s)} + H2O_{(l)} + 2e^- -> 2Ag_{(s)} + 2OH^-_{( aq)}}\] E0 = 0.34 V The cell potential will be
While charging lead storage battery
Among the following cells
I) Leclanche cell
II) Nickel – Cadmium cell
III) Lead storage battery
IV) Mercury cell
Primary cells are:
For the cell reaction
\[\ce{2Fe^{3+}_{( aq)} + 2l^-_{( aq)} -> 2Fe^{2+}_{( aq)} + l2_{( aq)}}\]
\[\ce{E^0_{cell}}\] = at 298 K. The standard Gibbs energy (∆G°) of the cell reactions is:
State Faraday’s Laws of electrolysis.
A current of 1.608A is passed through 250 mL of 0.5 M solution of copper sulphate for 50 minutes. Calculate the strength of Cu2+ after electrolysis assuming volume to be constant and the current efficiency is 100%.
Calculate the standard emf of the cell: \[\ce{Cd|Cd^{2+}||Cu^{2+}|Cu}\] and determine the cell reaction. The standard reduction potentials of Cu2+|Cu and Cd2+|Cd are 0.34 V and −0.40 volts respectively. Predict the feasibility of the cell reaction.
Derive an expression for the Nernst equation.
Explain the function of H2 – O2 fuel cell.
