Slide 1 : www.saitechinfo.com Difference between an orbit and orbital 1. Atomic Hypothesis Orbit: It is a definite circular path in which the electron is supposed to revolve around the nucleus.
Slide 2 : www.saitechinfo.com Difference between an orbit and orbital 1. Atomic Hypothesis Orbital: It is the three dimensional region around the nucleus in which the probability of finding the
electron is maximum.
Difference between an orbit and orbital : www.saitechinfo.com Difference between an orbit and orbital Orbit
Definite path of electron around nucleus
Circular path
Can accommodate 2n2 electrons (n = order of the orbit from nucleus)
Position and momentum of electron can be calculated at the same time Orbital
It is the three dimensional region around the nucleus in which the probability of finding the electron is maximum.
It has different 3 dimensional shapes. S – spherical, p – dump bell shaped
Can accommodate maximum 2 electrons
Not possible to find the exact position and momentum of electron at the same time 1. Atomic Hypothesis
Slide 4 : www.saitechinfo.com 2. Constituents of the atom ELECTRON: It is a negatively charged particle which occupies the space outside the nucleus in an atom.
PROTON: It is a positively charged particles present in the nucleus of an atom.
NEUTRON: It is a neutral particle of mass equal to the mass of proton.
Slide 5 : www.saitechinfo.com 3. Quantum numbers Designate and distinguish various atomic orbitals and electrons present in an atom
Four quantum numbers
Principal quantum number (n)
Azimuthal quantum number (l)
Magnetic quantum number (m)
Spin quantum number (s)
Slide 6 : www.saitechinfo.com 3. Quantum numbers Principal quantum number
Determines the energy shell in which the electron is revolving around the nucleus
Denoted by ‘n’, n = {1, 2, 3, …}
n =1 => K Shell
n =2 => L Shell
n =3 => M Shell
n =4 => N Shell
As n increases, the distance from the nucleus increases, its energy becomes higher an higher
The maximum no. of electrons in a major energy level is given by 2n2
Slide 7 : www.saitechinfo.com 3. Quantum numbers Principal quantum number
Slide 8 : www.saitechinfo.com 3. Quantum numbers Azimuthal quantum number
Represents the sub-shell
Denoted by ‘l’
l = n -1
l = { 0, 1, 2, 3,..}
If l = 0 => the electron is in the s orbital
If l = 1 => the electron is in the p orbital
If l = 2 => the electron is in the d orbital
If l = 3 => the electron is in the f orbital
Slide 9 : www.saitechinfo.com 3. Quantum numbers Azimuthal quantum number
Slide 10 : www.saitechinfo.com 3. Quantum numbers Magnetic quantum number
Represents the orientation of an atomic orbital in space
Denoted by ‘m’
m = 2l +1
m = {-l, 0, +l)
m = {…--2, -1, 0, +1, +2, ..}
If l = -2 => the electron is in the dxy orbital
If l = -1 => the electron is in the dyz orbital
If l = 0 => the electron is in the dyz orbital
If l = +1 => the electron is in the dx2 – y2 orbital
Slide 11 : www.saitechinfo.com 3. Quantum numbers Magnetic quantum number
Slide 12 : www.saitechinfo.com 3. Quantum numbers Spin quantum number
Represents the direction of the spin of electrons
Denoted by the symbol ‘s’
The electron may spin in the clockwise or anticlockwise direction
S = +1/2 or -1/2
Parallel spin or
Anti-parallel spin
Slide 13 : www.saitechinfo.com 3. Quantum numbers Spin quantum number