The continuous release of nuclear energy caused when on fission reaction triggers more nuclear reactions is a _

Answer is: nuclear chain reaction.

For example fission of heavy isotope uranium-238.

The decay chain of ²³⁸U is called the uranium series.

Decay start with U-238 and ends with Pb-206. There are several alpha and beta minus decays.

The half-life for the radioactive decay of U-238 is 4.5 billion years and is independent of initial concentration.

Alpha decay is radioactive decay in which an atomic nucleus emits an alpha particle (helium nucleus) and transforms into an atom with an atomic number that is reduced by two and mass number that is reduced by four.

In beta minus decay atomic number Z is increased by one, neutron is converted to a proton and an electron and an electron antineutrino.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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