Advertisements
Advertisements
Question
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.
Advertisements
Solution
\[\ce{E{^{\circ}_{{cell}}} = E{^{\circ}_{Ag_2O/Ag}} - E{^{\circ}_{{Zn^{2+}/Zn}}}}\]
= 0.344 − (−0.76)
= 1.104 V
For the cell reaction, n = 2,
∴ ΔrG° = \[\ce{-nFE{^{\circ}_{cell}}}\]
= –2 × 96500 × 1.104
= –2.13 × 105 CV mol–1
= –2.13 × 105 J mol–1
APPEARS IN
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?
Name the type of cell which was used in Apollo space programme for providing electrical power.
Define terms: Fuel cell
Define the following terms: Secondary batteries
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?
Give reasons:
Mercury cell delivers a constant potential during its life time.
Dry cells are commonly used in clocks, torches, calculators etc. They are the most familiar type of commercial cells.
- What acts as anode and cathode in dry cell?
- Which chemical compounds are filled between anode and cathode of this cell?
- Why do dry cells not have a long life?
