Which of these substances has a giant covalent structure?
Silicon dioxide
Buckminsterfullerene
A polymer
Which statement about different forms of carbon is correct?
Graphite and diamond conduct electricity but graphene does not
Graphite and graphene conduct electricity but diamond does not
Graphene and diamond conduct electricity but graphite does not
How many covalent bonds does each carbon atom in graphene form?
3
4
6
What is the formula of buckminsterfullerene?
C20
C40
C60
What is the shape of a nanotube?
Cylinder
Sphere
Flat sheet
What type of bond joins the atoms together in a polymer molecule?
Covalent
Ionic
Intermolecular forces
What properties do nanotubes have?
They are electrical insulators and they have low tensile strength
They conduct electricity and they have high tensile strength
They are electrical insulators and they have high tensile strength
Why is graphene a good conductor of electricity?
It has delocalised electrons that move between its layers
It has ions that are free to move
It has delocalised electrons that are free to move across its surface
Which statement best explains why diamond has a high melting point?
It has strong covalent bonds
A large amount of energy is needed to break its strong covalent bonds
A large amount of energy is needed to break its bonds
Which of these substances are slippery?
Graphite and buckminsterfullerene
Graphite and diamond
Diamond and silicon dioxide