3.1 Metal extraction and electrolysis

Front

What is reduction in a chemical reaction?

Back

Reduction is a gain of electrons by a reactant in any reaction.

Front

What is oxidation in a chemical reaction?

Back

Oxidation is a loss of electrons by a reactant in any reaction.

Front

What happens in a redox reaction?

Back

In a redox reaction, reduction and oxidation take place at the same time.

Front

What are ion-electron equations used for?

Back

Ion-electron equations can be written for reduction and oxidation reactions and can be combined to produce redox equations.

Front

What occurs during the extraction of metals?

Back

During the extraction of metals, metal ions are reduced forming metal atoms.

Front

How does the method of metal extraction depend on the reactivity series?

Back

The method used to extract a metal from its ore depends on the position of the metal in the reactivity series.

Front

What are the methods used for metal extraction?

Back

Methods used are: heat alone (for extraction of Ag, Au and Hg), heating with carbon or carbon monoxide (for extraction of Cu, Pb, Sn, Fe and Zn), and electrolysis (for extraction of more reactive metals including aluminium).

Front

What is electrolysis?

Back

Electrolysis is the decomposition of an ionic compound into its elements using electricity.

Front

Why must a d.c. supply be used in electrolysis?

Back

A d.c. supply must be used if the products of electrolysis are to be identified.

Front

What happens to positive and negative ions during electrolysis?

Back

Positive ions gain electrons at the negative electrode and negative ions lose electrons at the positive electrode.