Advertisements
Advertisements
Question
Name the type of cell which was used in Apollo space programme for providing electrical power.
Advertisements
Solution
One of the most successful fuel cells uses the reaction of hydrogen with oxygen to form water. This fuel cell was used for providing electrical power in the Apollo space programme. The water vapours produced during the reaction were condensed and added to the drinking water supply for the astronauts. In the cell, hydrogen and oxygen are bubbled through porous carbon electrodes into concentrated aqueous sodium hydroxide solution. Catalysts like finely divided platinum or palladium metal are incorporated into the electrodes for increasing the rate of electrode reactions. The electrode reactions are given below:
Cathode: O2(g) + 2H2O(l) + 4e- →4OH–(aq)
Anode: 2H2 (g) + 4OH–(aq) → 4H2O(l) + 4e–
Overall reaction being: 2H2(g) + O2(g)→ 2 H2O(l )
RELATED QUESTIONS
Draw neat and labelled diagram of dry cell.
Write cell reaction in lead storage battery during discharge.
Define electrochemical cell
Why does the cell potential of mercury cell remain constant throughout its life?
From the given cells:
Lead storage cell, Mercury cell, Fuel cell and Dry cell
Answer the following:
(i) Which cell is used in hearing aids?
(ii) Which cell was used in Apollo Space Programme?
(iii) Which cell is used in automobiles and inverters?
(iv) Which cell does not have long life?
What type of battery is mercury cell? Why is it more advantageous than dry cell?
Define the following terms: Secondary batteries
In the button cells widely used in watches and other devices, the following reaction takes place:
\[\ce{Zn_{(s)} + Ag2O_{(s)} + H2O_{(l)} -> Zn{^{2+}_{(aq)}} + 2Ag_{(s)} + 2OH^-_{ (aq)}}\]
Determine ΔrG° and E° for the reaction.
Without losing its concentration; ZnCl2 solution cannot be kept in contact with
Why does the cell voltage of a mercury cell remain constant during its lifetime?
