How can diamonds be made artificially? How do synthetic diamonds differ from natural ones? (b) Give any two differences between the properties of diamond and graphite. What causes these differences?

By subjecting the pure carbon to a very high pressure and temperature diamonds can be made artificially.

(b)(i) Diamond is hard in nature whereas graphite is soft.

(ii) Diamond can conduct electricity whereas graphite cannot it is a poor conductor of electricity.

The arrangement of carbon atom in these two are different, hence causes for the difference in properties.