Total number of orbitals associated with third shell will be __________.


o Sub-shells are actually sub-levels (energy levels) for an atom. The number of sub-shells is equal to the number of the principal shell i.e. the number of principal quantum number n. Also, the azimuthal quantum number l decides the orbital angular momentum ( presence of orbitals) and for a certain n, the values of l (subshells) would be 0 to (n-1)


o Hence e for 3rd shell or orbit, there are 3 sub-shells (0,1,2) that is, 3s, 3p and 3d.


• The 3s –subshell has only one orbital.


• The 3p-subshell has 3 orbitals.(px ,py , pz)


• The 3d-subshell has 5 orbitals(dxy,dyz,dxz,dz2,dx2-y2 )


Hence total orbitals are = 1 +3+5 = 9.

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