Question

How does critical mass play a role in nuclear reactions?

Answer 1

The critical mass is the point at which a chain reaction becomes self-sustaining if neutrons are lost at a faster rate than they are formed by fission, that reaction will not be self-sustaining.

Complete step by step answer:
To understand this question, we should firstly understand the critical mass in brief.
Critical mass : It is the smallest amount of fissile material needed for a sustained nuclear chain reaction. The critical mass of a fissionable material depends upon its nuclear properties, density, shape, enrichment, purity temperature and surrounding.
Critical mass is a nuclear chain reaction is the minimum mass of fissionable material that would sustain the nuclear chain reaction at a steady rate. The neutron reproduction factor K, ratio of production of neutrons is just equal to the rate of less neutrons.
The energy harnessed in nuclei is released in nuclear reaction. Fission is the splitting of a heavy nucleus into lighter nuclei and the nuclear fission is the combining of nuclei to form a bigger and heavier nucleus.

Note: Scientists have yet to find a method for controlling fission reactions. Fission reactions on the other hand is type used in nuclear power plants and can be controlled. Atomic bombs and hydrogen bombs are examples of uncontrolled nuclear reactions.