Answer: C. emits energy when it decays
Explanation:
An unstable nucleus can under go decay process or nuclear reactions - fission or fusion.
In nuclear reaction fusion, the nuclear mass increases. In fission, the nuclear mass decreases. The half-life of a nucleus undergoes no change. An unstable nucleus does not expel all its protons.
The unstable nucleus emits energy when it undergoes decay process. There are four possible decay process:
1.) Alpha decay: In this process, an alpha particle is emitted when a heavier nuclei decays into lighter nuclei.
2.)Beta-decay: In this process, a neutron gets converted into a proton and an electron releasing a beta-particle.
3.) Gamma ray emission: in this process, an unstable nuclei gives off excess energy by a spontaneous electromagnetic process and releases [tex]\gamma -radiations[/tex].
4.) Positron decay: In this process, a proton gets converted to neutron and an electron neutrino and releases positron particles.
All these decays are accompanied by emission of energy.
Thus, the correct option is C.
An unstable nucleus emits energy when it decays. The correct option is C.
The nucleus is a positively charged present in the center of an atom, negatively charged electrons revolve around us.
Radiation is emitted by the unstable nuclei of radioactive atoms. This results in the formation of a new atom and element.
This is known as radioactive decay.
It goes on like this until the forces in the unstable nucleus are equalized.
Thus, the correct option is C. emits energy when it decays.
Learn more about the nucleus
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