AP Chem Key-lime Pie- Polyatomic Ions & Simple Solubility Rules

Hypobromite

BrO⁻

Bromite

BrO₂⁻

Bromate

BrO₃⁻

Perbromate

BrO₄⁻

Hypochlorite

ClO⁻

Chlorite

ClO₂⁻

Chlorate

ClO₃⁻

Perchlorate

ClO₄⁻

Hypoiodite

IO⁻

Iodite

IO₂⁻

Iodate

IO₃⁻

Periodate

IO₄⁻

Acetate

C₂H₃O₂⁻

Cyanide

CN⁻

Thiocyanate

SCN⁻

Hydrogen Carbonate (bicarbonate)

HCO₃⁻

Dihydrogen Phosphate

H₂PO₄⁻

Hydrogen Sulfide (Bisulfide)

HS⁻

Hydrogen Sulfite (Bisulfite)

HSO₃⁻

Hydrogen Sulfate (Bisulfate)

HSO₄⁻

Permanganate

MnO₄⁻

Nitrite

NO₂⁻

Nitrate

NO₃⁻

Hydroxide

OH-

Peroxide

O₂²⁻

Carbonate

CO₃²⁻

Oxalate

C₂O₄²⁻

Chromate

CrO₄²⁻

Dichromate

Cr₂O₇²⁻

Hydrogen Phosphate

HPO₄²⁻

Sulfite

SO₃²⁻

Sulfate

SO₄²⁻

Thiosulfate

S₂O₃²⁻

Phosphate

PO₄³⁻

Mercury (I)

Hg₂²⁺

Mercury (II)

Hg²⁺

What cations are always soluble

Group 1 & NH₄⁺

Always Soluble Anions

NO₃⁻ ClO₄⁻ ClO₃⁻ C₂H₃O₂⁻ CH₃COO

Usually Soluble Anions

Cl⁻ Br⁻ I⁻ *Exceptions : (Ag⁺, Hg₂²⁺, Pb²⁺)

SO₄²⁻ *Exceptions (Ag⁺, Hg₂²⁺, Pb²⁺, Ca²⁺, Sr²⁺, Ba²⁺)

Usually Insoluble Anions

OH- *(Except w/ Group 1 & NH₄⁺, Ca²⁺, Sr²⁺, Ba²⁺)

CO₃²⁻ S²⁻ SO₃²⁻ CrO₄²⁻ PO₄³⁻ (Except w/ Group 1 Cations & NH₄⁺)