Fuel cells `:` Fuel cells are galvanic cells in which the chemical energy of fuel cell is directly converted into electrical energy. A type of fuel cell is a hydrogen `-` oxygen fuel cell. It consists of two electrodes made up of two porous graphite impregnated with a catalyst `(` platinum, silver, or metal oxide `).` The electrodes are placed in aqueous solution of `NaOH` . Oxygen and hydrogen are continuously fed into the cell. Hydrogen gets oxidized to `H^(o+)` which is neutralized by `overset(c-)(O)H, i.e.,` anodic reaction. At cathode, `O_(2)` gets reduced to `overset(c-)(O)H` Hence, the net reaction is The overall reaction has `DeltaH=-285.6 kJ mol^(-1)` and `DeltaG=-237.4 kJ mol^(-1)` at `25^(@)C` Suppose the concentration of hydroxide ioin in the cell is doubled, then the cell voltage will beA. Reduced by halfB. Increased by a factor of 2C. Increased by a factor of 4D. Unchanged

Fuel cells `:` Fuel cells are galvanic cells in which the chemical ene

1.	Fuel cells `:` Fuel cells are galvanic cells in which the chemical energy of fuel cell is directly converted into electrical energy. A type of fuel cell is a hydrogen `-` oxygen fuel cell. It consists of two electrodes made up of two porous graphite impregnated with a catalyst `(` platinum, silver, or metal oxide `).` The electrodes are placed in aqueous solution of `NaOH` . Oxygen and hydrogen are continuously fed into the cell. Hydrogen gets oxidized to `H^(o+)` which is neutralized by `overset(c-)(O)H, i.e.,` anodic reaction. At cathode, `O_(2)` gets reduced to `overset(c-)(O)H` Hence, the net reaction is The overall reaction has `DeltaH=-285.6 kJ mol^(-1)` and `DeltaG=-237.4 kJ mol^(-1)` at `25^(@)C` Suppose the concentration of hydroxide ioin in the cell is doubled, then the cell voltage will beA. Reduced by halfB. Increased by a factor of 2C. Increased by a factor of 4D. Unchanged
Answer» Correct Answer - d `E_(cell)` is independent of `[overset(c-)(O)H]` in this case.

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Define molar conductivity of a solution and explain how molar conductivity changes with change in concentration of a solution for a weak and a strong electrolyte.
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What are elementary reactions ?

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