Answer;
- Crystal structure
Explanation;
-Diamond and graphite are allotropes of carbon, they differ in physical properties.
-In graphite, carbon atoms are covalently bonded to form sheets or what we call hexagonal layers, and these sheets are held together by weak inter-molecular forces called vander waal forces. This makes the layers to slide over each other , a property that makes graphite soft and slippery.
-In Diamond, carbon atoms are bonded by strong covalent bonding forming a tetrahedron shaped solid of Diamond which makes it a very hard solid.