Nomenclatures

Ammonium = NH₄⁺

Know/Memorize

1-

CN^- cyanide

OH^- hydroxide

C₂H₃O₂^- acetate  (also CH₃COO^-)

NO₃^- nitrate

NO₂^- nitrite

*ClO₄^- perchlorate

*ClO₃^- chlorate

*ClO₂^- chlorite

*ClO^- hypochlorite

MnO₄^- permanganate

SCN^- thiocyanate

CSN^- isothiocyanate

N₃^- azide

2-

SO₄^2- sulfate

SO₃^2- sulfite

CO₃^2- carbonate

O₂^2- peroxide

CrO₄^2- chromate

Cr₂O₇^2- dichromate

C₂O₄^2- oxalate

3-

PO₄^3- phosphate

PO₃^3- phosphite

AsO₄^3- arsenate

BO₃^3- borate

*These and all halogens (F,Cl,Br and I) follow this pattern.

Metal ions

Monovalent Transition metals 

Zn²⁺ zinc cation

Ag⁺ silver cation

Cd²⁺ cadmium cation

Examples of polyvalent transition metal ions:

Fe²⁺ Iron(II)

Fe³⁺ Iron(III)

Cu⁺ Copper(I)

Cu²⁺ Copper(II)

Ni²⁺ Nickel (II)

Ni³⁺ Nickel(III)

Co²⁺ Cobalt(II)

Co³⁺ Cobalt(III)

Au⁺ Gold(I)

Au³⁺ Gold(III)

Pb²⁺ Lead(II)

Pb⁴⁺ Lead(IV)

Sn²⁺ Tin(II)

Sn⁴⁺ Tin(IV)

Pt²⁺ Platinum (II)

Pt⁴⁺ Platinum(IV)

Pd²⁺ Palladium(II)

Pd⁴⁺ Palladium(IV)

Hg²⁺ Mercury(II)

Hg₂²⁺ Mercury(I)

All transition metals except Ag/Zn/Cd should have roman numerals used in their name (there are some other exceptions to this that we will ignore).

For example: Cr, Rh, Pd and Mo would need roman numerals.

All main group metals except Sn and Pb (see above) have only one oxidation state based on their family location.  See your PT for these charges.