1 This question is about carbon and its compounds.
Fullerenes are molecules of carbon atoms.
The first fullerene to be discovered was Buckminsterfullerene (C60).
1-1 What shape is a Buckminsterfullerene molecule? [1 mark]
ANSWER
Spherical
1-2 Give one use of a fullerene. [1 mark]
ANSWER
For delivery of drugs throughout or specific parts of the body and/or cells – the drugs are often carried inside the hollow center of the fullerene molecule;
In lubricants to reduce friction when metal parts of machines move past each other – the spherical shape of the molecule helps and allows molecules to roll past each other hence reducing friction;
As catalysts – a lot of research is taking place into the use of fullerenes as catalysts and a wide range of potential applications are being found.
1-3 Propanone is a compound of carbon, hydrogen and oxygen. Figure 1 shows the dot and cross diagram for a propanone molecule.
Figure 1
Complete Figure 2 to show a propanone molecule. Use a line to represent each single bond. [1 mark]
Use Figure 1.
Figure 2
ANSWER
1-4 Determine the molecular formula of propanone.
Use Figure 1. [1 mark]
ANSWER
C3H6O
1-5 Propanone is a liquid with a low boiling point.
Why does propanone have a low boiling point? [1 mark]
ANSWER
The intermolecular forces are weak
1-6 Figure 3 represents the structure of graphite
Figure 3
Explain why graphite is:
a good electrical conductor
soft and slippery. [6 marks]
You should answer in terms of structure and bonding.
ANSWER
Graphite is a giant covalent bond structure and contains delocalized electrons (free electrons). These electrons can move throughout the structure of graphite, carrying charge from place to place and allowing graphite to be a good conductor of electricity;
Graphite is made up of layers of carbon atoms. Because these layers are weakly bonded together, they slide over each other easily. This is what makes graphite a soft and slippery material.
