Compound Nomenclature

Monatomic Ions

Single atoms that gain/lose electrons

Binary Ionic Compounds

Form when metal atoms combine with nonmetal atoms

Cations

Ions with a (+) charge

Anions

Ions with a (-) charge

Polyatomic Ions

Groups of 2 or more bonded atoms that have lost or gained electrons and have a net charge; generally anions

Monatomic Cations (Constant Charge)

Groups 1 (charge of +1) and 2 (charge of +2) ; includes Ag^+, Zn^2+, Cd^+, and Al^3+ as well

Monatomic Cations (Variable Charge)

Metal ions from groups 3-16

Monatomic Cations Nomenclature

1. For fixed charge, use element name followed by the word "ion"

2. For variable charge, use element name followed by roman numerals in parentheses to represent the charge

Monatomic Anions

Form from elements in groups 5-7

Monatomic Anions Nomenclature

1. Use name of the element and change the ending to "-ide"

2. Two polyatomic anions follow this rule ; OH- (Hydroxide) and CN- (Cyanide)

Ammonium

NH4^+ ; the only common polyatomic cation

Oxyanion

A class of polyatomic ion ; contains one nonmetal atom plus a variable number of oxygen atoms

Hydrogen Sulfite

HSO3^-

Hydrogen Sulfate

HSO4^-

Hydrogen Phosphite

HPO3^-2

Hydrogen Phosphate

HPO4^-2

Dihydrogen Phosphite

H2PO3^-

Dihydrogen Phosphate

H2PO4^-

Hydrogen Carbonate (AKA "Bicarbonate")

HCO3^-

Periodate

IO4^-

Iodate

IO3^-

Iodite

IO2^-

Hypoiodite

IO^-

Chromate

CrO4^2-

Dichromate

Cr2O7^2-

Permanganate

MnO4^-

Oxyanion Nomenclature

1. Per__ate: ClO4^-, BrO4^-, IO4^-

2. __ate: ClO3^-, BrO3^-, IO3^-, SO4^-, NO3^-, PO4^3-, CO3^2-

3. __ite: ClO2^-, BrO2^-, SO2^2-, NO2^-

4. Hypo__ite: ClO^-, BrO^-, IO^-

Hydrates

Ionic compounds that contain water molecules within their solid structure ; formula shows waters of hydration

Ex: CuSO4 x 5H2O (Copper (II) sulfate pentahydrate)

Anhydrous Form

The form taken after a hydrate has been heated

Ex: CuSO4 (Copper (II) sulfate)

Acids

When dissolved in water, release one or more H^+ ions and form an anion with a 1- charge for each H^+ ion released ; special class of H-containing molecular compounds

Ionizable Hydrogen Atoms

the H atoms released in water ; written at the beginning of the formula

Binary Acids

Contain H atoms and atoms from groups 16 and 17 ; the number of H atoms = the number of (-) charge of the anion

Oxyacids

Contain H atoms bonded to oxyanions

Acid Nomenclature

1. Binary acids follow the pattern of Hydro- root -ic acid

2. Oxyacids replace -ate ending with -ic, -ite with -ous, and retain the prefixes per- and hypo-

Acid Nomenclature Examples

1. "-ide" goes to Hydro__ic acid (HCl = Hydrochloric acid)

2. "-ate" goes to __ic acid (ClO4^- = Perchloric acid)

3. "-ite" goes to __ous acid (ClO2^- = Chlorous acid

Acetic Acid

HC2H3O2 or CH3COOH

Monoprotic Acid

When an acid has only 1 ionizable H atom

Polyprotic Acid

When an acid has more than 1 ionizable H atom

Main Rule for Naming Ionic Compounds

The cation is ALWAYS listed before the anion

Formulas of Polyatomic Ions

1. Use LCM to find subscripts needed to balance (+) and (-) charges

2. Enclose the polyatomic ion in parentheses and write subscript outside

Ex: Cr^3+ and CO3^2- have LCM of 6 ; 3+(2) = +6 so Cr2 and 2-(3) =-6 so (CO3)3 ; Cr2(CO3)3