Question

Copper in copper oxide does not liberate Sulphur Dioxide gas while copper in bronze Evolves Sulphur Dioxide gas with concentrated sulphuric acid. However for making statues copper is used in the form of bronze but not metallic copper or copper oxide .Explain why the same copper has such varied properties.

Answer 1

The solution is as follows:

1. The copper in copper oxide is bonded with oxygen. This bond with oxygen makes it unreactive towards sulphuric acid.

2 Copper in pure metallic state is very soft as the copper has small spaces in it.

3. Copper in bronze alloy has some tin with it. It is not bonded to tin but they are present together in the bronze alloy.

For making alloy, we use bronze form of alloy as it is hard and can be converted into strong statues. But pure copper and copper oxide are soft and cannot be used to make alloys.