Slide 1 : www.saitechinfo.com 4. Electronic configuration of atoms of elements ELECTRONIC CONFIGURATION: Distribution of electron in different orbitals of the atom of an element.
Slide 2 : www.saitechinfo.com 4. Electronic configuration of atoms of elements Principles and rules to write the electronic configuration Aufbau principle
Pauli’s exclusion principle
Hund’s rule of maximum multiplicity
Slide 3 : www.saitechinfo.com 4. Electronic configuration of atoms of elements Aufbau Principle Electrons are filled in the increasing order of energy level
Rule1: The electrons first occupy that orbital for which (n+1) value is lowest
Rule2: When (n+1) values for two orbitals are equal, then the electrons first occupy the orbital with lower value of n 1s < 2s < 2p < 3s < 3p < 4s < 3d < 4p < 5s < 4d < 5p
Slide 4 : www.saitechinfo.com 4. Electronic configuration of atoms of elements Pauli’s Exclusion Principle In an atom no two electrons can have the same set of four quantum numbers. different
Slide 5 : www.saitechinfo.com 4. Electronic configuration of atoms of elements Hund’s rule of maximum multiplicity Among the orbitals of same energy, electrons do not start pairing, until all these orbitals are singly occupied”. Hund’s rule is also called as the principle of minimum pairing and the principle of
maximum multiplicity. Case - 1 Case - 2 1s2 2s2 2px1 2py1 2pz1 1s2 2s2 2px2 2py1 2pz1
Slide 6 : www.saitechinfo.com 4. Electronic configuration of atoms of elements Illustration Hydrogen 1s1 Helium 1s2
Slide 7 : www.saitechinfo.com 4. Electronic configuration of atoms of elements Illustration Lithium 1s2 2s1 2px 2py 2pz Beryllium 1s2 2s2 2px 2py 2pz
Slide 8 : www.saitechinfo.com 4. Electronic configuration of atoms of elements Illustration Boron 1s2 2s2 2px1 2py 2pz Carbon 1s2 2s2 2px1 2py1 2pz
Slide 9 : www.saitechinfo.com 4. Electronic configuration of atoms of elements Illustration Nitrogen 1s2 2s2 2px1 2py1 2pz1 Oxygen 1s2 2s2 2px2 2py1 2pz1
Slide 10 : www.saitechinfo.com 4. Electronic configuration of atoms of elements Illustration Fluorine 1s2 2s2 2px2 2py2 2pz1 Neon 1s2 2s2 2px2 2py2 2pz2
Slide 11 : www.saitechinfo.com 4. Electronic configuration of atoms of elements Illustration