Memorization Guide for Ions and Solubility Rules

Type I Cations

Cations formed by Group 1 and Group 2 metals, as well as Silver, Aluminum, Zinc, Cadmium, and Ammonium.

Group 1 metals

Metals that form +1 cations.

Group 2 metals

Metals that form +2 cations.

Silver

Forms a +1 cation.

Aluminum

Forms a +3 cation.

Zinc and Cadmium

Form +2 cations.

Ammonium (NH4)

Forms a +1 cation.

Common Type II Cations

Cations that include Chromium, Manganese, Iron, Cobalt, Copper, Tin, and Lead, which can form multiple oxidation states.

Chromium, Manganese, Iron and Cobalt

Often form +2 and +3 cations.

Copper

Forms +1 and +2 cations.

Tin and Lead

Form +2 and +4 cations.

Mercury

Forms a +1 diatomic ion (Hg2+).

Common Monoatomic Ions

Ions that include halides, oxygen, sulfur, nitrogen, and phosphorus forming anions.

Halides

Form -1 anions (F, Cl, Br, I) in binary ionic compounds.

Oxygen and sulfur

Form -2 anions in binary ionic compounds.

Nitrogen and phosphorous

Form -3 anions in binary ionic compounds.

Prefixes for molecular compounds

Indicate the number of atoms in molecular compounds.

mono-

Indicates 1 atom.

di-

Indicates 2 atoms.

tri-

Indicates 3 atoms.

tetra-

Indicates 4 atoms.

penta-

Indicates 5 atoms.

Strong Acids

Include HCl, HBr, HI, HNO3, H2SO4, HClO3, HClO4, HIO4.

Solubility Rules for Salts

Guidelines for the solubility of various ions and compounds.

Strong Bases

Include LiOH, NaOH, KOH, RbOH, CsOH.

Common Polyatomic Ions

Include ions such as Acetate, Carbonate, Phosphate, and others.

Acetate

C2H3O2.

Carbonate

CO3.

Phosphate

PO4.

Bicarbonate

HCO3.

Chromate

CrO4.

Bisulfate

HSO4.

Dichromate

Cr2O7.

Bisulfite

HSO3.

Monohydrogen phosphate

HPO4.

Hypochlorate

ClO.

Sulfate

SO4.

Chlorate

ClO3.

Sulfite

SO3.

Chlorite

ClO2.

Peroxide

O2.

Cyanide

CN.

Permanganate

MnO4.

Dihydrogen Phosphate

H2PO4.

Hydroxide

OH.

Iodate

IO3.

Iodite

IO2.

Nitrate

NO3.

Nitrite

NO2.

Perchlorate

ClO4.