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Structure of Atom(Part 4)

 Discovery of Neutron:

Rutherford observed that atomic mass of the element could not be explained onvthe basis of the masses of electron and proton only. He predicted in 1920 that some neutral particle having mass equal to that of proton must be present in an atom. Thus scientists were in search of such a neutral particle. Eventually in 1932 Chadwick discovered neutron, when he bombarded alpha particles on a beryllium target. Hobserved that highly penetrating radiations were produced. These radiations were calleneutron.


Properties of neutron are as following:

i. Neutrons carry no charge i.e. they are neutral.

ii. They are highly penetrating.

iii. Mass of these particles was nearly equal to the mass of a proton.

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