Aufbau Principle, Pauli's Principle and Hund's Principle Class 11 Notes | EduRev

Chemistry for JEE

JEE : Aufbau Principle, Pauli's Principle and Hund's Principle Class 11 Notes | EduRev

The document Aufbau Principle, Pauli's Principle and Hund's Principle Class 11 Notes | EduRev is a part of the JEE Course Chemistry for JEE.
All you need of JEE at this link: JEE

Filling of Orbitals in atoms : 

The filling of electrons into the orbitals of different atoms take place on the basic of 3 principles :

Aufbau Principle: 

The electrons are added progressively to Various orbitals in the order of increasing energy, starting with the orbital of lowest energy.

Energy of Orbitals: 

(i) Hydrogen atom: In case of hydrogen atom, energy of orbital is mainly determined by principle quantum number.
Aufbau Principle, Pauli`s Principle and Hund`s Principle Class 11 Notes | EduRev

For H atom

1s < 2s = 2p < 3s = 3p = 3d < 4s = 4p

Aufbau Principle, Pauli`s Principle and Hund`s Principle Class 11 Notes | EduRev  Aufbau Principle, Pauli`s Principle and Hund`s Principle Class 11 Notes | EduRev


 (ii) Multi-electronic atoms: In case of multi-electronic atoms, energy of orbitals depends upon both n and l and hence energy of orbitals is compared on the basis of (n + l) rules generally.

⇒ n + l rule: 

(iii) As the value (n + l) increases the total energy of orbitals also increases.

Aufbau Principle, Pauli`s Principle and Hund`s Principle Class 11 Notes | EduRevFig: energy levels.

(iv) If value of (n + l) is same or different orbital then orbital with lower value of n, have lower energy.

Aufbau Principle, Pauli`s Principle and Hund`s Principle Class 11 Notes | EduRev

1s < 2s < 2p < 3s < 3p < 4s < 3d < 4p < 5s < 4d < 5p < 6s < 4f < 5d < 6p < 7s

Pauli Exclusion Principle: 

The principle states that no two electrons in an atom can have same set of all 4 quantum no. Therefore spin quantum No. have only two values therefore it can also be commented that orbital can have maximum two electrons with opposite spin.

Hund's Rule of Maximum Multiplicity: 

While filing the orbitals of same energy (i.e. orbitals of same subshell) pairing of electron start only when each orbital have got 1 electron that too with same spin or parallel spin.

Multiplicity is expressed as 2|s| + 1 where s represent total spin.

Aufbau Principle, Pauli`s Principle and Hund`s Principle Class 11 Notes | EduRevAufbau Principle, Pauli`s Principle and Hund`s Principle Class 11 Notes | EduRev 2|s| + 1 = 2

Aufbau Principle, Pauli`s Principle and Hund`s Principle Class 11 Notes | EduRevAufbau Principle, Pauli`s Principle and Hund`s Principle Class 11 Notes | EduRev, 2|s| + 1 = 2

Aufbau Principle, Pauli`s Principle and Hund`s Principle Class 11 Notes | EduRevAufbau Principle, Pauli`s Principle and Hund`s Principle Class 11 Notes | EduRev, 2Aufbau Principle, Pauli`s Principle and Hund`s Principle Class 11 Notes | EduRev + 1 = 4 (It has maximum multiplicity) 


Offer running on EduRev: Apply code STAYHOME200 to get INR 200 off on our premium plan EduRev Infinity!

Related Searches

Pauli's Principle and Hund's Principle Class 11 Notes | EduRev

,

Important questions

,

Pauli's Principle and Hund's Principle Class 11 Notes | EduRev

,

past year papers

,

shortcuts and tricks

,

study material

,

ppt

,

Objective type Questions

,

Free

,

Viva Questions

,

Extra Questions

,

practice quizzes

,

Aufbau Principle

,

Sample Paper

,

mock tests for examination

,

MCQs

,

pdf

,

Semester Notes

,

Previous Year Questions with Solutions

,

Aufbau Principle

,

video lectures

,

Pauli's Principle and Hund's Principle Class 11 Notes | EduRev

,

Exam

,

Aufbau Principle

,

Summary

;