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Electronic configurations


                   Electronic configurations

 Electronic configuration- electronic configuration the process of dividing electrons equally into orbits of an element.
Use of electronic configuration- electronic configuration can be used to find valency, charge, and so on.
Sub atomic particles present in an atom-
Sub atomic
Particles 
      Charge
Mass of particle
Electron
 Negative ‘-’
 9.109390 x10-31 kg
Proton
Positive ‘+’
 1.672623 x 10-27 kg
Neutron
No charge
 1.672623 x 10-27 kg
  
How to doelectronic configuration-
Step 1- find the atomic number of electron in an element.
Step 2- find the the no. Of electron in the orbit of an atom.
Formula for finding the number of electrons in orbit is -
n means serial number of orbit like – 1,2,3.....etc.
Step 3- divide electrons according to no. Of electron in orbit is - 
Some facts about electronic configuration-
Ø Orbits are denoted in electronic configuration by K,L,M...etc. or 1,2,3....etc.
Ø It helps to find valency of an element.
Ø It helps to find charge of an element.
Ø It helps to make chemical formulas.
Electronic configuration from 1 to 20 elements-
Atomic number
elements
Electronic cofigration
              ----
------
K
L
M
N
O
P
1
Hydrogen
1





2
Helium
2





3
Lithium
2
1




4
Beryllium
2
2




5
Boron
2
3




6
Carbon
2
4




7
Nitrogen
2
5




8
Oxygen
2
6




9
Fluorine
2
7




10
Neon
2
8




11
Sodium
2
8
1



12
Magnesium
2
8
2



13
Aluminum
2
8
3



14
Silicon
2
8
4



15
Phosphorus
2
8
5



16
Sulfur
2
8
6



17
Chlorine
2
8
7



18
Argon
2
8
8



19
Potassium
2
8
8
1


20
Calcium
2
8
8
2


                                   OR
NUMBER
 ELEMENT
ELECTRON CONFIGURATION
1
Hydrogen
1s1
2
Helium
1s2
3
Lithium
[He]2s1
4
Beryllium
[He]2s2
5
Boron
[He]2s22p1
6
Carbon
[He]2s22p2
7
Nitrogen
[He]2s22p3
8
Oxygen
[He]2s22p4
9
Fluorine
[He]2s22p5
10
Neon
[He]2s22p6
11
Sodium
[Ne]3s1
12
Magnesium
[Ne]3s2
13
Aluminum
[Ne]3s23p1
14
Silicon
[Ne]3s23p2
15
Phosphorus
[Ne]3s23p3
16
Sulfur
[Ne]3s23p4
17
Chlorine
[Ne]3s23p5
18
Argon
[Ne]3s23p6
19
Potassium
[Ar]4s1
20
Calcium
[Ar]4s2



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