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InterviewSolution
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What are the consequences that lead to the development of quantum mechanical model of an atom ? |
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Answer» Solution :In 1923 Louis de-Broglie proposed that like light MATTER also has dual character . It exhibits wave as well as particle nature . He derived an equation to calculate the wave-length`(lamda)` of the wave associated with a particle of mass m , nmoving with velocity v and it is given by `lamda=(h)/("mv")" (or)"lamda=(h)/(p)` 'h' is Planck's constant and P is momentum of the particle . It may be noted that wave character has significance only in the case of sub-microscopic particles such as electrons. The precise location of a wave cannot be predicted as a wave is not located at a particular point but EXTENDS in space . Thus the wave nature of electron puts some restriction in finding the position precisely . W . Heisenberg put forward this limitation in the form of uncertainty principle . According ot Heisenberg, "It is not possible to determine simultaneously and accurately both the position and momentum of a small moving particle , such as electron." It can be EXPRESSED mathematically as , `DELTA"x"xxDeltapge(h)/(4pi)` `Delta"x"xxmDeltavge(h)/(4pi)` where `Deltax` = uncertainty in position `Deltap` = uncertainty in momentum m = mass of particle `Deltav` = uncertainty in velocity h = Planck's constant. The uncertainty principle is due to the direct consequence of dual nature of matter . Amicroscopic object such as electron has both observable wave - like and particle - like properties . The behaviour of such particles cannot be explained on the basis of science called quantum mechanical MODEL of atom was developed . Quantum mechanics is a theroretical science that takes into account the dualnature of matter . |
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