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Structure of Atom — Chemistry STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceChemistryStructure of Atom5 Marks
Question
Why was a change in the Bohr Model of atom required? Due to which important development (s), concept of movement of an electron in an orbit was replaced by, the concept of probability of finding electron in an orbital? What is the name given to the changed model of atom?
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Answer

In view of the shortcoming of the Bohr,s model, attempts were made to develop a more suitable and general model for atoms. Two important devlopments which contributed significantly in the formulation of such a model were:
  1. Dual behavior of matter,
  2. Heisenberg uncertainty principle.
Werner Heisenberg, a German physicist in 1927, stated uncertainty principle which is the consequence of duel behaviour of matter and radiation. One of the important implication of the Heisenberg Uncertainty Principle is that it rules out existence of definite paths or trajectories of electrons and other similar particles.
Quantum mechanics is the theoretical science that deal with the study of the motions of the microscopic objects that have both observable wave like and particle like and properties. The name of the changed model of atom is Quantum Mechanical Model of atom

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