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I am school student. In my school text book there is a fact about diamond. That is
Each carbon atom is covalently bonded to four other carbon atoms. A lot of energy is needed to separate the atoms in diamond. This is because covalent bonds are strong, and diamond contains many covalent bonds. This makes diamond's melting point and boiling point very high.
If a diamond is a single molecule, how does a single molecule melt? Is that fact correct? Please tell me the answer!