Temporary Core Particle :
The particles that reside temporarily in the atoms of any element are called Temporary Core Particles. Notable among the temporary particles are positron, meson, pion, muon, neutrino, antineutrino, etc.
Isotopes :
In 1913, scientist Soddy first introduced the term isotope. Atoms that have the same atomic number but different mass numbers due to having different numbers of neutrons in their nuclei are called isotopes of each other. That is, atoms of the same element with the same number of protons, but different mass numbers are called isotopes of each other, for example, hydrogen has three isotopes. These are-
Features of Isoto:
(i) They are atoms of the same element
(ii) Atomic or proton numbers, but neutron numbers are different numbers.
(iii) Isotopes occupy the same position in the atomic periodic table of elements (isotopes of the same name are given for this.
(iv) Same chemical religion, but different observed in some religions. For example, heavier isotopes have higher melting or boiling points.
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