Networks and Nano Flashcards
One Property Shared by Graphite and Diamond
High Boiling point
One Property differes for graphite and diamond
Electrical conductivity
Why would fullerene nanoparticles be expected to be good conductors of electricity?
The Delocilasied electrons are more able to move through the dispersion forces of the fulllerene nano particles because each carbon atom is not covelantly bonded to all 4 of its electrons unlike diamond .
Diamond
Hardest substance due to all 4 carbon molecules coveantly bonding to one another making a rigid internal lattice structre
Properties of Covelant Network Lattices (Diamond)
Very hard, difficult to scratch and have high melting points. Since there are no free moving ions or electrons they are non conductors of electricity. Chemically inhert and insoulble in water
Graphite
Flat sheets of carbon on top of each other by dispersion forces. Graphite only covelantly bonds to 3 of its carbon atoms making it a more 2 dimensional lattice. Graphite is a good conductor of electricity because of its free moving outer shell that is not bonded to any other carbon atom
Difference betweeen Graphite and Graphene
Graphite are flat layers of carbon that are held together by weak dispersion forces which allows them to easily slide over each other. Graphene on the other hand is one flat sheet of carbon and is incredibly strong
Network Covalent Lattice
Strong Bonding (High Melting point) and No charged particles (No electrical conductivity)
Other Covalent networks
Silicon dioxide
Why would silicon have lower melting point than diamond
Silicon Atoms are larger than carbon atoms. This makes the si-si bonds length longer than the C-C bonds and are not as strong.
Silicon
A continuous covalent lattice of Si atoms. Each Si is bonded to 4 other Si atoms in a tetrahedral arrangment
Covalent Molecular Substance
Relatively weak bonds between molecules (Low melting point)
