valencies

Appendix 2

Students should be able to recognise and write the formula of the following ions and molecules:

Ion name

Formula

 

Ion name

Formula

ammonium

 

bromide

caesium

 

chloride

hydrogen

 

cyanide

lithium

 

dihydrogenphosphate

potassium

 

ethanoate (acetate)

rubidium

 

fluoride

silver

 

hydrogencarbonate

sodium

 

hydrogensulfate

barium

 

hydroxide

calcium

 

iodide

cobalt(II)

 

nitrate

copper(II)

 

nitrite

iron(II)

 

permanganate

lead(II)

 

carbonate

magnesium

 

chromate

manganese(II)

 

dichromate

nickel(II)

 

hydrogenphosphate

strontium

 

oxalate

zinc

 

oxide

aluminium

 

sulfate

chromium(III)

 

sulfide

iron(III)

 

sulfite

 

 

 

nitride

 

 

 

phosphate

 

Common molecules that have non-systematic names:

Molecule name

Formula

ammonia

water

O

hydrogen peroxide

ethanoic acid

hydrochloric acid

nitric acid

carbonic acid

sulfuric acid

sulfurous acid

phosphoric acid

 

 

     

 

Table 1


                                                 Symbols and names of monoatomic ions.

 

 

1+

 

2+

 

3+

 

4+

 


gold(I)


Au+ 


mercury(II)
tin(II)
cadmium(II)

+
Hg2+
Sn2+
Cd2+


gold(III)



Au3+

 

tin(IV)
lead(IV)

 

Sn4+
Pb4+

 

1-

 

 

hydride

 

H-

 

 

Table 2

 

                    Formulae and names of polyatomic ions.

 

1-

 

2-

 

3-

 


dihydrogenphosphate
perchlorate
chlorate
chlorite
hypochlorite


H2PO4-
ClO4-
ClO3-
ClO2-
ClO-


peroxide


O22-











1+

 

2+

 

 

 


 

ammonium   

 

NH4+

 

mercury(I)
 

 

Hg22+

 

 

 

 

Table 3

 

                Formulae and names of molecular substances

                                   

                  Elements                                                     Compounds

                  hydrogen                 H2                               carbon monoxide                                     CO

                  nitrogen                   N2                               carbon dioxide                                          CO2

                  oxygen                      O2                               sulfur dioxide                                             SO2

                  fluorine                    F2                                sulfur trioxide                                            SO3

                  chlorine                    Cl2                               hydrogen sulfide                                      H2S

                  bromine                   Br2                              hydrogen fluoride                                   HF

                  iodine                     I2                                 hydrogen chloride                                   HCl

                  phosphorus           P4                                hydrogen bromide                                  HBr

                  sulfur                         S8                                hydrogen iodide                                       HI

                                                                                          nitrogen monoxide                                 NO            (nitric oxide)

                                                                                          nitrogen dioxide                                       NO2

                                                                                          dinitrogen monoxide                              N2O          (nitrous oxide)

                                                                                          dinitrogen tetraoxide                             N2O4

                                                                                       hypochlorous acid                                    HClO