Valency

The combining capacity of an atom or a radical is called its valency. It is measured in terms of hydrogen atoms or oxygen atoms. Valency of an atom or a radical is the number of hydrogen atoms or double the number of oxygen atoms which will combine with it.
==Radicals with their valencies and symbols==
===Basic or Electropositive Radicals===
Name 	Symbol 	Valency
Aluminium	Al 	3
Ammonium 	NH 	1
Antimony 	Sb 	3
Barium 	Ba 	2
Bismuth 	Bi 	3
Cadmium 	Cd 	2
Calcium 	Ca 	2
Chromium 	Cr 	3
Cobalt 	Co 	2
Copper 	Cu (cuprous) 	1
 	Cu (cupric) 	2
Hydrogen 	H 	1
Iron 	Fe (ferrous) 	2
 	Fe (ferric) 	3
Lead 	Pb (plumbous) 	2
 	Pb (plumbic) 	4
Magnesium	Mg 	2
Manganese	Mn (manganous) 	2
 	Mn (manganic) 	3
Mercurous	2}} (Mercury I)	2
Mercuric 	Hg (Mercury II)	2
Nickel 	Ni 	2
Potassium	K 	1
Silver 	Ag 	1
Sodium 	Na 	1
Strontium	Sr 	2
Tin 	Sn (Stannous) 	2
 	Sn (Stannic) 	4
Zinc 	Zn 	2
===Acid or Electronegative Radicals===
Name 	Symbol	Valency
Fluoride 	F 	1
Chloride 	Cl 	1
Hypochlorite 	ClO 	1
Chlorate 	ClO 	1
Bromide 	Br 	1
Hypobromite 	BrO 	1
Iodide 	I 	1
Sulphide 	S 	2
Sulphite 	SO 	2
Hypoiodite 	IO 	1
Iodate 	IO 	1
Bisulphite 	HSO 	1
Sulphate 	SO 	2
Bisulphate 	HSO 	1
Thiosulphate 	SO 	2
Nitrite 	
NO 	1
Nitrate 	NO 	1
Nitride 	N 	3
Hydroxide 	OH 	1
Oxide 	O 	2
Hydride 	H 	1
Peroxide 	O 	2
Carbonate 	CO 	2
Bicarbonate 	HCO 	1
Carbide 	C 	4
Phosphate 	PO 	3
Phosphite 	HPO 	2
Phosphide 	P 	3
Borate 	BO 	3
Acetate 	ChCOO 	1
Cyanide 	CN 	1
Manganate 	MnO 	2
Permanganate 	MnO 	1
Chromate 	CrO 	2
Dichromate 	CrO 	2
Ferrocyanide 	Fe(CN)	4
Ferricyanide 	Fe(CN)	3
Arsenite 	AsO 	3
Arsenate 	AsO 	3
Zincate 	Zn 	2
Meta-Aluminate	AlO 	1
Aluminate 	AlO 	3
Stannate 	SnO 	2
Silicate 	SiO 	2
If possible, it is advised to learn the symbols and valencies by heart which can be of great help in studying chemistry further.
Category:Chemistry