mayankdevnani 2 years ago How to find the valency of an element?? Also give me some examples...

1. nubeer

valancey is something or the spots left to be filled by electrons in a the last shell

2. nubeer

if you have some question already u can tell that way would be easier to tell ..

3. mayankdevnani

no, i have not any particular question just give some examples.

4. mayankdevnani

@vishweshshrimali5 @ganeshie8

5. mayankdevnani

ok. nubeer what is the valency of mg

6. Areesha.1D

1) Find out the electronic configuration. That is the number of electrons for that ion. Electronic config. for Mg is 2,8,2. 2) Now see how many electrons you get in the last orbit. 3) That number become your valency. Mg is +2. If the last is more than four then it means it is the negative ion and hence check how many electrons are needed to stabilize that ion. For eg. Chlorine is 2,8,7. Therefore to complete the octet, it needs 1 electron and hence valency of chlorine is -1. You need to see weather the number of electrons in last orbit is more than, less than or equal to 4. If more than it is a negative ion and its valency can be -1,-2,-3. If less than 4 than valency can be +1,+2,+3. And if equal to 4 than it is a metalloid which acts as a metal as well as a non-metal. Eg.--- silicon. Valency of Na is +1 coz its electronic config. is 2,8,1. And now you find out for V as a practice. Valency is the combining capacity of an element and valence electrons are the number of electrons in the last orbit which are lost, gained or shared during the course of a reaction.

7. mayankdevnani

just copy and paste @Areesha.1D

8. mayankdevnani

@nubeer

9. Areesha.1D

@mayankdevnani yeah, i brought you information you needed, yet were incapable of finding yourself.

10. nubeer

lol what she is said is right.. ok few things you should know is The valency of an element is the measure of electrons it needs or needs to loose to obtain a stable structure.. what is stable structure.. stable structure is when any atom have 8 electrons in the last shell.

11. nubeer

so if we take Mg.. it has configuration 2,8,2 means it has 2 electrons in the outer most shell.. whether Mg can loose 2 electrons or gain 6 more.. it's easy to loos 2 rather then gaining 6 electrons so Mg preferes to loose.. so when Mg loose it will get a charge of+2 on it.

12. nubeer

group 1 to 3 looses electrons these groups also called metals.. and the non-metals looses electrons.

13. mayankdevnani

ok..so what is the valency of cl

14. nubeer

Cl.. 2,8,7.. tell me what u think its easy for him to loose or gain to achieve it's outer shell to be filled by 8 electrons.?

15. Areesha.1D

@nubeer let him figure it out.

16. mayankdevnani

looseing right!!

17. nubeer

yes @Areesha.1D i have told him all the details won't tell answer will just walk him through..

18. nubeer

hmmm nooo.. do u think he will just break 7 parts of it structure and not just having 1 more electron.. llook u have to think loosing and gaining is same it's not about tough.. think which is easier way to have 8 electrons in outer shell.. whther he can just gain 1 and have 8 or loose 7 electrons.

19. Areesha.1D

@nubeer exactly! have fun llol

20. nubeer

:P

21. mayankdevnani

hmmm, he can just gain 1 and have 8 .right

22. nubeer

yes.. so its easy and when any atom gain an electron it get's a positive charge.. so what charge you think Cl will get?

23. mayankdevnani

i don't know!!! plz tell me and give me another example and i can do this..k

24. nubeer

look when electron is loose positive charge appears and when gains a negative charge appears.. so Cl gain 1 electron so it will get -1 charge.. u can take any if by any chance hypothetcially Cl gains 4 electron then it gets -4 charge and if it loose 7 electron so will get +7 charge.. get it? do for Al.

25. mayankdevnani

so finally what is the valency of cl

26. mayankdevnani

@nubeer

27. mayankdevnani

@sauravshakya

28. nubeer

i think i mentioned the valency in the last post.. did you read it? it has just gain 1

29. Areesha.1D

omg -_- @mayankdevnani put a BIT of effort in, look how well @nubeer explained !!!

30. mayankdevnani

kkk...my chance to find the valency of al..plz wait

31. mayankdevnani

al its electronic confugiration is |dw:1354100607658:dw|

32. nubeer

yes.

33. nubeer

have to make 8 in last shell.. so right now 3 in last shell so easy to loose or gain?

34. mayankdevnani

gain

35. nubeer

hmm how much have to gain to get 8? it would have to take 5 more .. so no.. its better to loose look group 1-3 will loose electrons.. and group 5-8 gains electrons.. made more easy for u.

36. nubeer

now look in which group Al is in the periodic table.

37. mayankdevnani

13

38. nubeer

13? or 3?

39. mayankdevnani

13 is atomic number

40. Areesha.1D

Oh lord

41. mayankdevnani

@nubeer

42. nubeer

nooo not atomic number.. do you know about groups in a periodic table and sorry.. my internet is a liittle slow.

43. mayankdevnani

mention not

44. nubeer

so what about group numbers do you know of them?

45. mayankdevnani

so its valency is 3

46. nubeer

hmm well yes.

47. mayankdevnani

but howz that...it loose its electrons

48. nubeer

yes how many it loose? 3 .. and when any atome looses it gets a positive charge..

49. nubeer

http://www.chem4kids.com/files/elem_pertable.html this is something about groups if you don't know.

50. mayankdevnani

oh i see

51. mayankdevnani

now its my chance give me some example

52. nubeer

ok try Ba, Ca, Na , K, Cr, B, N, Br.. try any u want.

53. mayankdevnani

first Ca

54. mayankdevnani

electronic confugiration-|dw:1354101724985:dw| so it looses electrons and have a positive charge of 2+ right!!

55. nubeer

yes right..

56. mayankdevnani

thnx....

57. mayankdevnani

last its silicon

58. mayankdevnani

electronic configuration-|dw:1354101886249:dw| so it looses electrons and have a positive charge of 4+ right!!!

59. nubeer

yes..

60. mayankdevnani

thnx...

61. mayankdevnani

i understand very nicely.. thnx @nubeer and @Areesha.1D

62. mayankdevnani

and also give me medal for my hard work

63. nubeer

i am glad.. you are welcome ..

64. Areesha.1D

lol thank the Dear Lord above XD congratulations!