Page 23 - E-Science Prep1 2024-2025 t2 Unit1_Neat - Copy

? The valences of some metallic, non-metallic elements and
atomic groups:

Valency Metallic element Non-metallic element
Monovalent (1) Li+ H-
K+ Cl-
Na+ F-
Br-
Divalent (2) Ca+2 I-
Mg+2 O-2
Trivalent (3) Ni+2 S-2
Tetravalent (4) Zn+2
Al+3 C-4

Valency Atomic group
Monovalent (1) (OH)- Hydroxide
(HCO3)- Bicarbonate
Divalent (2) (NO3)- Nitrate
Trivalent (3) (NO2)- Nitrite
(NH4)+ Ammonium
(SO4)-2 Sulphate
(CO3)-2 Carbonate
(PO4)-3 Phosphate

38

Second Term