Bsc subject chemistry (inorganic sem-1) complete notes

Unit 1 Atomic structure

Idea of De-broglie matter waves: 

 Einstein in 1905 suggested that light has dual character . 

In 1924 De-broglie proposed that matter also has dual character ( it means behave as waveas well as particle)  .

 Principle:  The principal of wave and particle duality of matter is known as De- broglie principle. 

 If substance behavea particle it's energy is given by Einstein 

       E= mc^2     1eq.

 if substance behave like a wave it's energy given by plancks quantum theory. 

       E= hv           2eq. (here v is called nue  ) 

from 1 & 2 eq. 

we get hv=mc^2

  & also know v= c/√ 

 let is √ called lamda  

 now (h×c) /√ =mc^2

or √= h/m×c

 Applying relation to an eletron moving with velocity(V). 

  so √= h/m×V

&we know that p= m×V

        or √= h/p

This relation is called De-broglie wave eq. 

 Significance of de broglie Relationship

 In our daily life we come across with macroscopic object so De- broglie relationship has no significance in our daily life. 

 De-broglie relationship is applicable to all moving particle but it is significance to microscopic particle ,because just

    √ { 1/m                ( where { called directly proportional sign) 

1. for macroscopic particle since mass is large . so √  comes out too be small, not to be measured .

2. for microscopic particle since mass is small,.  so √ comes out to be large & can  be measured experimently. 

   
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