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Atomic Structure and Chemical Bonding — CHEMISTRY STD 9 — Question

ICSE BoardEnglish MediumSTD 9CHEMISTRYAtomic Structure and Chemical Bonding5 Marks
Question
Give the postulates of Bohr's atomic model
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Answer

Atom has a central nucleus surrounded by electrons.
The electrons revolve around the nucleus in definite circular paths called orbits.
Each orbit has fixed energy. Therefore, these orbits are also known as energy levels or energy shells.
These orbits or energy levels are represented either by a number 1, 2, 3,... known as the principal quantum number (n) of the orbit or by K, L, M,....
There is no change of energy of electrons as long as they keep revolving in the same energy level and the atom remains stable. Electrons can jump from the higher orbit to the lower orbit when they lose energy and jump to the next when they gain energy.

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