The extraction of Au by leaching with NaCN, involves both oxidation and reduction. Justify giving chemical equations.

Which can undergo both oxidation and reduction:

Which reaction involves oxidation nor reduction ?

Give two examples of oxidation-reduction reaction.

Why is leaching of gold by metal cyanides carried out in the presence of oxygen? Give the chemical equation. Name the metal used as reducing agent.

Give a chemical reaction which involves homogeneous catalysis.

(i) Name a compound of (a) transition metal which is used in the manufacture of sulphuric acid. (b) transition metal that is used in Haber's process for the manufacture of ammonia. (c ) transition metal that have light sensitive properties and act as valuable source in photographic industry. (ii) Write the equations which are involved in the oxidation of hydrogen sulphide to sulphur by potassium permanganate solution.

Extraction of silver from its ore involving NaCN , air and an active metal is known as :

The common method of extraction of metals from oxide ores involves :