Q.

Quantum numbers are useful to locate the position of an electron in an atom. There are four types of quantum numbers. They are
1) Principal quantum number
2) Azimuthal quantum number
3) Magnetic quantum number
4) Spin quantum number
1) Principal quantum number:
i) It was proposed by Niels Bohr
ii) It was denoted by a letter ‘n’
iii) Its values are 1, 2, 3…. and also designed by K, L, M…..
iv) It signifies size and energy of an orbit.
2) Azimuthal quantum number:
i) It was proposed by sommerfeld.
ii) It was denoted by a letter ‘l’.
iii) Its values are 0 to (n–1).
iv) It signifies the shape of the orbital
l = 0 ; s-orbital; spherical in shape
l = 1 ; p-orbital; dumbbell in shape
l = 2 ; d-orbital; double dumbbell in shape
l = 3 ; f-orbital; four fold dumbbell
3) Magnetic quantum number :
i) It was proposed by lande.
ii) It was denoted by a letter ‘m’.
iii) Its values are –l to + l including “0”
iv) It signifies spatial orientation of an electron in an orbital.
v) It was explains “zeeman effect” and “stark effect”
4) Spin quantum number:
i) It was proposed by “uhlenbeck” and Goud smith.
ii) It was denoted by a letter ‘s’
iii) Its values are +½ and −½ .
iv) It signifies the direction of spin of an electron
v)