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Chemistry — STRUCTURE OF THE ATOM
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ACADEMIA AETERNUM
तमसो मा ज्योतिर्गमय · Est. 2025
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Chemistry | Chemistry Class 9
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Frequently Asked Questions
Atoms have a nucleus made of protons and neutrons, with electrons arranged in shells around it.
James Chadwick discovered the neutron in 1932.
Protons, neutrons, and electrons.
The number of protons in the nucleus of an atom.
The sum of protons and neutrons in the atom’s nucleus.
Atoms of the same element with different numbers of neutrons.
Atoms of different elements with the same mass number but different atomic numbers.
The number of electrons an atom can gain, lose, or share to become stable.
Electrons revolve in fixed orbits (shells) around the nucleus without losing energy.
Atomic number is protons; mass number is protons + neutrons.
Electrons fill shells in order, with each shell holding up to \(2n^2\) electrons.
J.J. Thomson.
The gold foil experiment.
Electrons in the outermost shell of an atom.
They have the same number of protons and electrons.