Giant Covalent Substances
1.Some covalently bonded substances from giant structures.
2.These substances have very high melting points.
3.Diamond and graphite are both forms of carbon but have many different properties.
Giant Covalent Substances.
atoms of some elements can form several covalent bods. These atoms can join together in giant covalent structures (sometimes called 'macromolecules').
Every atom in the structures joined to several other atoms by strong covalent bonds. It takes an enormous amount of energy to break down the lattice and so these substances very high melting points.
Diamond (a form of carbon) and silica (silicon dioxide) have regular three-dimensional giant structures and so they are very hard and transparent.