Naming Binary Compounds

Binary Ionic Compounds (Type I)

1. The cation (positively charged ion; Na^+, Al³⁺) is always named first and the anion (negatively charged ion; Cl^-, O^2-) second.
2. A monatomic (meaning one-atom) cation takes its name from the name of the element.  For example, Na⁺ is called sodium in the names of compounds containing this ion.
3. A monatomic anion is named by taking the root of the element name and adding -ide.  Thus, the Cl^- ion is called chloride, the S^2- ion is called sulfide, and the O^2- ion is called oxide.

Some common monatomic cations and anions are shown below

Cation	Name	Cation	Name		Anion	Name	Anion	Name
H+	Hydrogen	Li+	Lithium		H-	Hydride	F-	Fluoride
Na+	Sodium	K+	Potassium		Cl-	Chloride	Br-	Bromide
Cs+	Cesium	Be2+	Beryllium		I-	Iodide	O2-	Oxide
Mg2+	Magnesium	Ca2+	Calcium		S2-	Sulfide	Se2-	Selenide
Ba2+	Barium	Al3+	Aluminum		N3-	Nitride	P3-	Phosphide
Zn2+	Zinc	Ag+	Silver		As3-	Arsenide	C4-	Carbide

Give correct names for these Type I binary compounds

KCl	MgO
K2O	AlCl3
CaO	BaS
MgCl2	Al2S3
NaH	SrF2
ZnS	MgI2
RbBr	CaSe
Al2O3	BaBr2
Na3N	CsCl
Ca2C	Mg3P2
KI	CaCl2

Give correct formulas for these Type I binary compounds

calcium iodide	magnesium phosphide
calcium hydride	sodium chloride
magnesium fluoride	barium oxide
cadmium bromide	aluminum arsenide
sodium nitride	calcium sulfide
rubidium oxide	potassium selenide
barium nitride	sodium iodide
lithium chloride	lithium sulfide
silver sulfide	calcium carbide
aluminum nitride	sodium hydride
cesium fluoride	magnesium nitride

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