1 ) What is total number of radical and angular nodes present in 5f orbital ?

1 ) What is total number of radical and angular nodes present in 5f orbital ?

Solution : -

Radical and angular nodes : -

Region where electron density in an orbital is zero .

5f orbital : -

Principal quantum number is number of shells . So , n = 5 .

Azimuthal quantum number is number of sub shells . So , L = 3 .

∴  Azimuthal quantum number  for different sub shells : -

s = 0  ,  p = 1  ,  d = 2   ,  f = 3 .

So , now we can find radical and angular nodes : -

Radical nodes : -  n – L – 1  =  5 – 3 – 1  =  1 .

Angular nodes : -  L  =  3 .

 

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2 ) The number of nodes for 4f orbital is : -

A ) 3 ,                                                         B ) 4 ,

C ) 6 ,                                                         D ) None of these ,

Correct Answer : -   A ) 3 ,

Solution : -

For 4f : -  n = 4  ,  L = 3 .

So , number of angular nodes  =  L  =  3 .

Number of radial nodes  =  n – L – 1  =  4 – 3 -1  =  0 .

So , total number of nodes  =  3 + 0  =  3  ,  Answer .

 

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3 ) Find the magnetic moment of a divalent ion in aqueous solution , if its atomic number is 25 ?

A ) 1 BM ,                                                  B ) 5.9 BM ,

C ) 17 BM ,                                                          D ) None of these ,

Correct Answer : -   B ) 5.9 BM ,

Solution : -

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4 ) How many spherical nodes are present in 4s orbital in a hydrogen atom ?

A ) 1 ,                                                         B ) 2 ,

C ) 3 ,                                                         D ) None of these ,

Correct Answer : -   C ) 3 ,

Solution : -

So , Spherical nodes  =  n – L – 1 ,

∴  For  4s : -  n = 4  and  L = 0 ,

So , Spherical nodes  =  4 – 0 – 1  =  3 nodes ,   Answer .

 

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