Expert: Amy - 12/14/2004

Question
Which metal is most likely obtained by the electrolysis of its fused salts?
(1)Au
(2)Ag
(3)Li
(4)Zn
The answer is 3. And I think it has something to do with Li being a regular metal in group 1 while the other 3 are transitional metals in groups 11 & 12. But I don't understand the connection if there is one

Answer
Hi heres some information about reduction of metal oxides to get the metal. This should clarify things a little

Thanks,
Amy



The ores of most metals contain the metal in an oxidized state. The form in which a metal occurs is related to the chemical activity of the metal and the stability of its compounds.

Reduction of the ore is necessary to obtain the metal, the method of reduction depending on the activity of the metal and the type of ore.

The most active metals are obtained from their fused compounds by electrolytic reduction.

2NaCl(fused) + electricity --> 2Na + Cl2 (Na = group 1 metal)

Metals that form relatively stable compounds can be liberated from their compounds by stronger reducing agents. For example, in the production of chromium, aluminum reduces the chromium oxide.

2 Al + Cr2O3 --> Al2O3 + 2Cr

Moderately active metals like zinc and iron are obtained by reduction of their oxides by carbon (coke) or carbon monoxide.

ZnO + C + heat --> Zn + CO

Fe2O3 + 3CO + heat --> 3CO2 + 2Fe

Supplementary Information
In general, compounds of metals that occur in nature have high stability and low solubility in water.

Groups 1 and 2 metals are obtained by electrolysis of their fused salts.

Many metals are found as sulfides and carbonates. These ores are converted to the oxide form and then reduced by carbon.