NAMING Ionic COMPOUNDS Jenny Casares Xandra Garanzuay

IONIC BONDING Opposites Attract Metal - Nonmetal Cation - Anion Ex. NaCl MgBr2 metal-nonmetal metal-nonmetal + -

Binary Compounds Example: aluminum oxide 1. Write cation symbol first, then anion. aluminum oxide Al3+ O2-

Binary Compounds Example: aluminum oxide 2. Compare value of charges. Al3+ O2-

Binary Compounds Example: aluminum oxide 2. Compare value of charges. Al3+ O2- Two (2) aluminum ions are needed to balance out three (3) oxide ions. Al3+ Al3+ O2- O2- O2- +3 x 2 = +6 and -2 x 3 = -6 Charges cancel, or +6 – 6 = 0, Neutral!

Binary Compounds Example: aluminum oxide 3. Check subscripts for smallest whole number ratio: Formula is: Al2O3 (cannot be reduced further)

Stock System Some metals are multivalent, having more than one cation. Example: iron(II) iron(III) Fe2+ Fe3+

Stock System To distinguish different ionic charges, Roman numerals are used. Example: iron(II) iron(III) Fe2+ Fe3+ II=+2 III=+3

Stock System Example: iron(II)oxide 1. Write cation symbol first, then anion. iron(II) oxide Fe2+ O2-

Stock System Example: iron(II)oxide 2. Compare value of charges. Fe2+ O2- One (1) iron ion is needed to balance out one (1) oxide ion. +2 x 1 = +2 and -2 x 1 = -2

Stock System Example: iron(II)oxide 3. Check subscripts for smallest whole number ratio: Formula: FeO

Let’s practice! 1. Write cation first, then anion. 2. Compare charges. 3. Check subscripts for smallest whole number ratio.

IONIC BONDING Opposites Attract Polyatomic Ion – Polyatomic Ion Cation – Anion Ex. NaOH (NH4)2CO3 metal-polyatomic polyatomic-polyatomic + -

Polyatomic Compounds Example: ammonium carbonate 1. Write cation symbol first, then anion. ammonium carbonate NH4+ CO32-

Polyatomic Compounds Example: ammonium carbonate 2. Compare value of charges. NH4+ CO32-

Polyatomic Compounds Example: ammonium carbonate 2. Compare value of charges. NH4+ CO32- Two (2) ammonium ions are needed to balance out one (1) carbonate ion. NH4+ NH4+ CO32- +1 x 2 = +2 and -2 x 1 = -2 Charges cancel, or +2 – 2 = 0, Balanced!

Polyatomic Compounds Example: ammonium carbonate 3. Use “( )” around polyatomic ions when there is more than one. Check subscripts for smallest whole number ratio. Formula is: (NH4)2CO3 *Polyatomic ions are a bonded unit and cannot be separated or reduced. * A “1” subscript is understood and not written.

Let’s practice! 1. Write cation first, then anion. 2. Compare charges. 3. Check subscripts for smallest whole number ratio.

COVALENT BONDING Cooperative Bonding Before you can name correctly, you must be able to distinguish between an ionic and a covalent compound. THERE ARE NO METALS IN A COVALENT COMPOUND !!!!!

Nonmetal + Nonmetal Ex. C + O = CO carbon monoxide COVALENT BONDING Nonmetal + Nonmetal Ex. C + O = CO carbon monoxide

Prefixes 1 - 10 Mono - 1 Di - 2 Tri - 3 Tetra - 4 Penta - 5 Hexa - 6 Hepta - 7 Octa - 8 Nona - 9 Deca - 10

Using Prefixes If there is only 1 of the first atom in a compound, you do not add mono If there is only 1 of the second atom in a compound, you MUST put mono before the name Always add prefixes to any element name with 2 or more atoms

EXAMPLES P4O10 CO2 SO2 C2H6 CF4

Let’s practice!