Here we see the electron configuration for the element helium.  This electron configuration provides us with the following information:

• The large number "1" refers to the principle quantum number "n" which stands for the energy level.  It tells us that the electrons of helium occupy the first energy level of the atom........

• The letter "s" stands for the angular momentum quantum number "l".  It tells us that the two electrons of the helium electron occupy an "s" or spherical orbital.

• The exponent "2" refers to the total number of electrons in that orbital or sub-shell.  In this case, we know that there are two electrons in the spherical orbital at the first energy level.

Sublevel	# of orbitals	Maximum number of electrons
s	1	2
p	3	6
d	5	10
f	7	14

Principle energy level (n)	Type of sublevel	Number of orbitals per type	Number of orbitals per level(n2)	Maximum number of electrons (2n2)
1	s	1	1	2
2	s	1	4	8
	p	3
3	s	1	9	18
	p	3
	d	5
4	s	1	16	32
	p	3
	d	5
	f	7

ab yeh tho theek hai............now lets see abt some rules on how 2 fill the orbitals....!!!!!!!!!!!!!




Order of Filling Sublevels with Electrons

the energy sublevels are filled in a specific order that is shown by the arrow diagram seen below:

HOPE U ALL LIKED IT...................!!!!!!!!!!!!!!!!!!!!!!!