Ion Charges: Group 1 = 1+ ions etc. Group 7 = 1-.
• Need to know also Zn2+ and Ag+
.
• Transition Metals: Form several ions with different charges. Ionic charge shown with Roman
numeral in name.
• Binary Compound: Compounds containing two elements. For the second element add suffix –ide.
Metal ion (+ve ion) always comes first.
• Polyatomic Ion: An ion containing more than one atom bonded together. Ammonium is NH4
+
.
Hydroxide is OH-
. Nitrate is NO3
–
. Carbonate is CO3
2-
. Sulphate is SO4
2-
, Hydrogencarbonate HCO3
–
,
manganate (VI) MnO4
2−
, phosphate PO4
3-
• Diatomic Molecules: Molecules which contain two atoms of same element bonded together. E.g.
hydrogen, nitrogen, oxygen, halogens, S8 and P4.
