Chemistry

Structure of the Atom


Relation Between Valency and Valence Electrons


The valency of an element depends on the number of valence electrons (outermost electrons) in its atom because only the valence electrons take part in chemical bonding.The valency of an element is either equal to the number of valence electrons in its atom or equal to the number of electrons required to complete eight electrons in the valence shell.For example, sodium has 1 valence electron and the valency of sodium is also 1. So,in the case of sodium, the valency is equal to the number of valence electrons in its atom. In general,the valency of a metal element is equal to the number of valence electrons in its atom.That is,
Valency of a metal = No. of valence electrons in its atom
Let us discuss the case of non-metals now. Chlorine has 7 valence electrons but its valency is not 7. Chlorine atom requires 1 electron to complete the 8 electron structure, so the valency of chlorine is 1. Thus,in the case of chlorine, valency is equal to the number of electrons required to complete 8 electrons in the valence shell. In general,the valency of a non-metal element is usually equal to eight minus the number of valence electrons in its atom.That is,
Valency of a non-metal = 8 - No. of valence electrons in its atom
There is one exception to this rule and that is the valency of hydrogen. The valency of hydrogen is equal to the number of valence electrons, which is 1 (though hydrogen is a non-metal element).

--- >>>

Notes


Structure of the Atom - Notes
1. Drawback of Rutherford’s Model of the Atom
Show Notes
2. Rutherford’s Experiment - Discovery of Nucleus
Show Notes
3. 4.Isotopes of Neon.
Show Notes
4. 3.Isotopes of Oxygen.
Show Notes
5. For the symbols H, D and T,tabulate three sub-atomic particles found in each of them.
Show Notes
6. Radioactive Isotopes
Show Notes
7. Characteristics of a Neutron
Show Notes
8. (d) Covalency of Nitrogen
Show Notes
9. Arrangement Of Electrons In The Atoms
Show Notes
10. Limitations of Rutherford's model of the atom
Show Notes
11. Characteristics of an Electron
Show Notes
12. Structure of The Atom - Study Points
Show Notes
13. All about Names of the Chemical Elements
Show Notes
14. Mass Number
Show Notes
15. 1. Isotopes of Hydrogen.
Show Notes
16. How to learn naming Chemical Formulae?
Show Notes
17. Characteristics of a Proton
Show Notes
18. Nucleus
Show Notes
19. (b) Valency of Magnesium
Show Notes
20. 2.Covalency
Show Notes
21. Thomson's Model Of The Atom
Show Notes
22. (e) Valency of Oxygen
Show Notes
23. (a) Covalency of Hydrogen
Show Notes
24. Isotopes
Show Notes
25. Rules for writing of distribution of electrons in various shells for the first 18 elements
Show Notes
26. Comparison between Proton, Neutron and Electron
Show Notes
27. Electronic Configurations of First 20 Elements
Show Notes
28. Covalency of Oxygen
Show Notes
29. 2.Isotopes of Carbon.
Show Notes
30. (d) Valency of Chlorine
Show Notes
31. Discovery of Neutron
Show Notes
32. Bohr's Model Of The Atom
Show Notes
33. The Physical Properties of the Isotopes of an Element are Different
Show Notes
34. Rutherford's Model Of The Atom
Show Notes
35. Atomic Number
Show Notes
36. Charged Particles in Matter
Show Notes
37. (a) Valency of Sodium
Show Notes
38. Discovery Of Electron
Show Notes
39. All the Isotopes of an Element Have Identical Chemical Properties
Show Notes
40. Discovery of Proton
Show Notes
41. Valaency Of Elements
Show Notes
42. Relationship Between Mass Number and Atomic Number
Show Notes
43. (f) Valency of Nitrogen
Show Notes
44. Electronic Configurations of Noble Gases (or Inert Gases)
Show Notes
45. Cause of Chemical Combination
Show Notes
46. Covalency of Carbon
Show Notes
47. Covalency of Chlorine
Show Notes
48. Applications of Radioactive Isotopes
Show Notes
49. Relation Between Valency and Valence Electrons
Show Notes
50. Electronic Configurations of Elements
Show Notes