carbon

Question 1

able of catenation; meaning?

Answer 1

can form bonds with atoms of the same element , carbon to carbon

Question 2

meaning of allotrope

Answer 2

different forms in which the element can exist. different chemical and physical properties.

Question 3

molecular characteristics of diamond

Answer 3

-covalent macromolecular
-carbons are sp3
- spr orbitals on neighbouring C atoms overlap to form single bonds (sigma bonds)
- angle of 109.5 between each C
each carbon has 4 sigma bonds

Question 4

characteristics of graphite

Answer 4

• covalent macromolecular
• C are sp2 hybridised, with one 2p orbital unhybridised
• overlap of sp2 forms single bonds.
• each C is bonded to 3 C atoms
• C-C bond is shorter than the C-C in diamond

Question 5

what occurs with the unhybridised 2p orbitals of graphite?

Answer 5

• the 2p orbitals overlap sideways to give a massive delocalised pi electron system above and below the plane of sheet of atoms

this cloud of e- prvides additional bonding (pi bonding). thus C-C bonds in graphite are stronger than in diamond

Question 6

bonds in graphite

Answer 6

atoms within the sheet are held by strong covalent bonds (stronger than diamond)
sheets are held by id id van der waals forces. delocalised e move around in the sheet, large temporary dipoles are set up.

Question 7

structure of bucky ball

Answer 7

60 carbon atoms arranged in spherical structure with pentagonal and hexagonal rings
covalent simple molecular bonding, C60 molecules ar eheld by id id forces of attraction

Question 8

characteristics of bucky ball

Answer 8

soluble in non polar solvents
only id id forces need to be broken
electrical insulator