Allotropes of Carbon

• Elemental carbon can exist in several different forms called ______________.

• Each allotrope had ___________________ properties.

• Why?

Allotropes of Carbon

Diamonds

Diamonds crystallize as a face-centered cubic crystal

Properties• _______ covalent network structure.

• All carbons form ________________ bonds

• No plane of weakness making the diamond exceptionally hard.

• Are the electrons are localized or delocalized?

Diamond ctd:

• Form deep within the earths crust under extreme temp and pressure.

• Come to the surface via volcanoes.• About a quarter of all Diamonds mined

are used in jewellery.• The rest are used in drilling and cutting

equipment.• ______________ in polar and non-polar solvents

because molecular bonds are ________________ than any intermolecular forces

Graphite

Graphite:• Each carbon

makes _____ bonds.

• The 4th pair of electrons are ____________

• Built up from 2D layers.

Graphite ctd:

•Used in pencils.•Illustration by Jennifer Parks,

done in coloured pencil.•Used in electrodes and

batteries.

Properties of Graphite

• Different from Diamond

• Same as Diamond

Energy diagram for conversion of graphite to diamond

• Which is more stable?

Is this reaction endothermic or exothermic?

Buckyballs

• Third allotrope of carbon.• ___________________-

named after an architect who popularized the geodesic dome.

• Consists of _______ carbons atoms arranged in hexagons and pentagons giving a geodesic spherical structure. ___________

• Is able to partially conduct electricity.

• Why

• Can be used as a “cage” to transport and protect molecules.