Hy!
Steemit friends!
I am going to explain basic concept of valency in chemistry.
VALENCY:
The combining powerof an element with other element is called its valency.Valency depends upon the number of electron in valence/last shell of atom of an element.
In covalent compounds the valency is number of covalent bond formed by an atom of element.e.g in HCl valency of H is 1 and also valency of Cl is 1 .In NH3 the valency of N is 3
In ionic compound the valency is the number of electrons lost or gained by an atom.The atom having 1 to 3 electrons in valence shell have tendancy to lose their electrons and forms positive ions.The atom having 5 to 7 electron in their valence shell have tendency to gain ekectrons to form negtive ion.
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