What is an example of Polymorphism?

Answer 1

A polymorph is defined as same composition, different chemical structures. Quartz, cristobalite, and tridymite are examples of polymorph because they are three different minerals with the same chemical composition. Graphite and diamond are also good examples of polymorphism. They both contain carbon atoms, but they have extremely different properties because of the condition in which they formed. Diamond forms where extreme pressures and temperatures produce its compact structure. On the other hand, graphite forms under comparatively low pressures and it has weekly bonded carbon sheets that create its greasy feel. The difference in conditions makes diamond much harder than graphite and graphite much more useful as a lubricant.