Question

Graphite is a soft solid lubricant extremely difficult to melt. The reason for this anomalous behaviour is that graphite ______.

Options

• is an allotropic form of diamond

• has molecules of variable molecular masses like polymers

• has carbon atoms arranged in large plates of rings of strongly bound carbon atoms with weak interplate bonds

• is a non-crystalline substance

Answer 1

Graphite is a soft solid lubricant extremely difficult to melt. The reason for this anomalous behaviour is that graphite has carbon atoms arranged in large plates of rings of strongly bound carbon atoms with weak interplate bonds.

Explanation:

Graphite has a two-dimensional sheet structure. These diverse sheets are kept together by van der Waals attraction. Because of these weak forces of attraction, one layer might slide over the other. As a result, graphite is soft and works well as a lubricant. Graphite is particularly difficult to melt due to the strong C – C covalent bonds.