Inorganic and Applied Chemistry

Download free books at BookBooN.com

Inorganic and Applied Chemistry

while the following half cell reaction takes place at the cathode:

2 MnO 2 (s) + 2 H 2 O(l) + 2 e-  Mn 2 O 3 (s) + 2 OH-(aq)

In respect to the acid dry cell battery the life time for the alkaline battery is significantly longer as zinc

corrodes slower in basic than in an acid environment.

Another type of battery is the mercury battery often formerly used in pocket calculators. The mercury

battery has a zinc electrode while mercury oxide HgO are oxidised in the basic environment consisting of

typically KOH and Zn(OH) 2. The figure below shows the set-up of the mercury dry cell battery.

Figure 6- 8: Mercury battery

Sketch of the set-up of a basic mercury dry cell battery.

Electrochemistry