Describe the essential properties of the atomic nucleus. Compare these with the properties of the electron.

(i) The nucleus is present at the center of the atom and has protons and neutrons in it.


(ii) Nucleus determines the overall charge on the atom because of the presence of the positively charged protons.


(iii) It is also responsible for the chemical properties of the element like the valency of the atom, reactivity of the element towards any other element and also the atomic number and mass number of the atom.


(iv) While the neutron are electrically neutral it contributes to the mass of the atom.


(v) The atomic mass is the numeric sum of the protons and neutrons. The mass of an atom is responsible for the physical properties like the melting point, boiling point, density, etc.


(vi) The nucleus remains stationery at the centre of atom, on the other hand the electron revolves around the nucleus due to the attraction between the positively charged nucleus and negatively charged electron.


(vii) As the electron moves around the nucleus, it also spins on its axis. The mass of an electron is considered to be negligible as compared to the nucleus but it is responsible for the valency of the atom and determines the atom’s capability to take part in any chemical reaction.


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