Question

1. A salt bridge is described as containing a large number of chemically inert ions. Explain why these ions must be chemically inert?
2. What is critical mass? How does critical mass effect the nature of a nuclear reaction?
Thanks a lot

Answer 1

1) a salt bridge generally contains KCl or KNO3 or NH4NO3 which are nonreactive with the anodic and cathodic half cell solutions or ions. If they react with any of the ions in anode or cathode compartment, the resultant oxidation or reduction potentials would be altered. Therefore this will strongly affect the overall cell voltage.

2)This is one of the important parameters for a nuclear reaction to occur instantly. In nuclear chemistry, critical mass can be defined as " the minimum amount of fissile material needed to achieve a chain reaction under set standard conditions.

In a nuclear fission reaction, every reaction produce 2 or 3 neutrons and these all are not useful to continue the subsequent chain reactions and some of them are lost. In order to continue the nuclear fission reaction continuously, the nuclear fission rate should be slow compared to the rate of neutrons lost in the nuclear reaction. This can be achieved by taking a critical amount of reacting material.

These critical mass phenomena place a major roll in the manufacturing of nuclear bombs.