## ashna 3 years ago can anyone explain me quantum numbers ?

1. ashna

@akash123

2. sgurjant

n = the shell l (total nodes) = subshell which is 0...n-1 in which so s = 0 p = 2 d= 3... radial nodes are n-l-1

3. ashna

i want all the 4 quantum numbers explained with one of their main characteristic please !

4. sgurjant

what do u mean? im studying this right now too... ill give an example? lets say u have k which is potassium...1s2 2s2 2p6 3s2 3p6 4s1 the prinicple quantum number would be 4 because its form the 4th shell. the subshell would be n-1 radial nodes is n-L-1

5. sgurjant

http://www.youtube.com/watch?v=VAnZtvYG51c check this out it definitely helps

6. ashna

i know this one , what am asking is for the simple defenition of all 4 quantum nos , the principal , azimuthal , spin and magnetic quantum no's and their characteristic , i have a theory test that's y :|

7. ashna

@sgurjant ty :)

8. akash123

so for telling the orientation of a particular orbit...we need a 3rd quantum no...that is magnetic quantum no eg px, py, pz l=1 for p so m = -l to +l m=-1,0,+1 this corresponds to px, py and pz

9. akash123

fine?

10. ashna

yes right !

11. akash123

similarly l=2 for d sub-shell, so m=-2 to +2 m=-2,-1,0,+1,+2 so d orbital has 5 orientation

12. akash123

now the last one---spin quantum no u know that each of px, py and pz contain 2 electrons

13. ashna

okay dxy dyz dzx dz^2 and dx^2-y^2 right ?

14. ashna

yes

15. akash123

so for distinguishing between the two electrons in an orbital (px, py or pz) , we need a fourth quantum number.

16. ashna

okay

17. akash123

u can understand it by assume that electron is spinning clockwise or anticlockwise. so s= either+1/2 or -1/2

18. ashna

okay , how do i use it , like how do they ask question regarding spin quantum no ?

19. akash123

u will be asked...write all the quantum nos of an electron in any atom..

20. ashna

can yu give a qn and its answer ?

21. akash123

|dw:1350458194009:dw|

22. akash123

look for ur text book.