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Carbon allotropes. The physical properties depend on the chemical bonding. Diamond. Strong covalent bonds in 3 dimensions Every carbon atom bonds 4 other carbon atoms in a crystalline lattice The hardest material known. Diamond . Hard, colourless, insulator
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Diamond Strong covalentbonds in 3 dimensions Everycarbon atom bonds 4 other carbon atoms in a crystallinelattice The hardest material known
Diamond • Hard, colourless, insulator • Tetrahedral, giant structure • Covalent bond => sp3 orbitals (HL)
Graphite The double bondsare delocalised and move- electricconductivity in the plane The planes bond withweakintermolecular bonds- van derWaals bonds The layersmoveeasily- graphitecolours Animation
Graphite • Slippery, black, electricity conductor • Layers of fused six-membered rings. Each carbon surrounded by three others in a planar trigonal arrangement => sp2 + p-orbital (HL) • The p-orbital is perpendicular to the layer and give close packed p-orbitals • stabilise the layers • Delocalisation of electrons => electrical conductivity
Fullerenesoch nanotubes Nanotubes
Fullerene, C60 • Spherical molecule. Looks like a football. 12 pentagons and 20 hexagons. • Bonds: C60 –hydration C60H60 (C2H4 + H2 C2H6 ; 1 H2 / double bond) Each carbon has a double bond