Chemical tables...

[Externet]

Are the "electromotive series" and the "electronegativity" the same tables with different reference points ?

Are both Pauling's ?

 

What is carbon electromotive series value ?

Edited June 22, 2008 by Externet
corrected

[DeanK2]

Electronegativity is the ability of an atom to attract a pair of electrons in a covalent bond. The nuclear charge and the atomic radius determine the electronegativity - the larger the nuclear charge, the more it will attract a bonding pair of electrons. The smaller the atomic radius, the greater the attraction between the nucleus and the bond electrons.

 

On descending a group, the effective nuclear charge on an atom remains the same, but the size increases. Therefore the top member is more electronegitve, as it is smaller and attracts the bonding electrons more.

Therefore, an electronegative atom would not be readily oxidised. Therefore an electronegative metal would be low down in the electromotive series.

 

The electromotive series begins with the metal most easily oxidized, i.e., the metal with the greatest electron-donating tendency, and ends with the metal least easily oxidized. The tendency to be oxidized is not an absolute quantity; it can only be compared with the tendency of some other substance to be oxidized. In practice, the tendency to be oxidized, called the oxidation potential and expressed in volts, is measured relative to a standard hydrogen electrode, which is arbitrarily assigned an oxidation potential of zero.

 

ELECTROMOTIVE HAS NOTHING TO DO WITH ELECTRONEGATIVITY FOR A REFERENCE OF VALUES: BUT EACH CAN BE EXPRESSED BY EACH OTHERS DEFINITION.