Very large molecules
Graphene
A form of carbon consisting of a single layer of carbon atoms joined together in hexagonal rings. is another form of carbon. Its structure resembles a single layer of A form of pure carbon in which all the atoms are bonded to three others in giant sheets which can slide over each other.. Graphene has a very high The temperature at which a solid changes into a liquid as it is heated. and is very strong because of its large regular arrangement of carbon The smallest part of an element that can exist. joined by A bond between atoms formed when atoms share electrons to achieve a full outer shell of electrons.. Like graphite it To allow electricity, heat or other energy forms to pass through. electricity well because it has Electrons that are not associated with a particular atom, eg in a metal, outer electrons can be free to move through the solid. Subatomic particle, with a negative charge and a negligible mass relative to protons and neutrons. that are free to move across its surface.
Fullerenes
A Molecules of carbon with hollow shapes. Their structures are based on hexagonal rings of carbon atoms. is a Refers to a substance made up of molecules, so it contains small groups of atoms, of a set size, held together by covalent bonds. form of the A substance made of one type of atom only. carbon. Two examples of fullerenes are Long cylindrical molecules made from carbon atoms joined together by covalent bonds. and Molecules comprising carbon atoms joined together to form spherical or nearly spherical hollow structures..
Nanotubes
A nanotube resembles a layer of graphene, rolled into a tube shape. Nanotubes have high The tension a material can withstand without breaking., so they are strong in Pulling force exerted by each end of an object such as a string or rope. and resist being stretched. Like graphene, nanotubes are strong and conduct electricity because they have delocalised electrons.
Buckyballs
Buckyballs are spheres or squashed spheres of carbon atoms. They are made up of large molecules so are not classed as giant Giant regular arrangement of atoms, with a repeating pattern, held together by covalent bonds.. Weak Weak attractive forces between molecules. When a simple molecular substance melts or boils, it is the intermolecular forces that are broken (not the covalent bonds in each molecule). exist between buckyballs. These need little The capacity of a system to do work or the quantity required for mechanical work to take place. Measured in joules (J). For example, a man transfers 100 J of energy when moving a wheelbarrow. to overcome, so substances consisting of buckyballs are slippery and have lower The temperature at which a solid changes into a liquid as it is heated. than graphite or A form (allotrope) of pure carbon in which all the atoms are bonded to four others in a giant tetrahedral network structure which is very strong. Diamond is the hardest known natural substance, has a very high melting point and does not conduct electricity..
Polymers
Simple A large molecule formed from many identical smaller molecules known as monomers. consist of large A collection of two or more atoms held together by chemical bonds. that contain chains of carbon atoms of no set size.
More guides on this topic
- Equations and formulae - Edexcel
- Hazards and risks - Edexcel
- Atomic structure - Edexcel
- The periodic table - Edexcel
- Ionic compounds - Edexcel
- Simple molecular substances - Edexcel
- Metals and non-metals - Edexcel
- Chemistry calculations - Edexcel
- Mole calculations (higher) - Edexcel
- Sample exam questions - key concepts in chemistry - Edexcel