Chemical Bonds

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5

Group VIIA – accept one e- to form –1 (Cl-1)

Slide 34

Naming IONIC compounds

Anions – suffix – “ide”

So Cl- is chloride

Oxygen O2- is OXIDE

S2- is SULFIDE

Cations

For Na+, Ca2+, the name of the ion is the same except refer to the ion.

So SODIUM ION or SODIUM CATION

NaCl - sodium chloride

CaCl2 - calcium chloride

Slide 35

Covalent, charged compounds - MOLECULAR IONS

Positive Molecular Ions

End the name with “ium” or “onium”

NH4+ is ammonium, H3O + is hydronium

Negative Molecular Ions

Slide 36

The transition elements are chemically quite different from the metals in the “A” block, due to differences in electronic configuration

For example, Fe can loose two or three electrons to become Fe2+ and Fe3+, respectively.

Transition Elements

Slide 37

To identify the charge of Fe in a compound the following nomenclature is used.

Fe2+ is iron(II)

Fe3+ is iron (III)

So iron(III) chloride is FeCl3

An older scheme differentiated between the lower and higher charge by ending the name of the element with “ous” to indicate the lower charge and “ic” for the higher.

ferrous chloride => FeCl2

ferric chloride => FeCl3

However, this convention does not indicate the numerical value of the charge.