C2 Bonding, Structure and the properties of Matter Flashcards
What is metallic bonding?
When 2 metals bond.
What is ionic bonding?
When a metal and a non-metal bond. You can show them in dot and cross diagrams.
What is an ionic substance?
Ionic substances have high melting/boiling points due to the strong ionic bonds/electrostatic forces. They can conduct electricity when molten or dissolved in solution. Ions are free to move in these states, and they carry charge. Ionic compounds are also called salts.
What is covalent bonding?
When non-metals bond to each other. Atoms share electrons to gave full outer shells. Every covalent bond consists of a pair of shared electrons.
What are simple covalent structures?
They have low boiling points due to weak intermolecular forces which need to be overcome. This means that not a lot of energy is needed to break the bonds. They cannot conduct electricity.
What are giant covalent structure?
Consists of repeating units of atoms to make what are giant molecules. E.g. diamond or silicon dioxide. They have very high melting points due to the strong covalent bonds.
What is an alloy?
An alloy is a mixture of metals: different size atoms disrupt the lattice so layers cannot slide over each other easily.
Describe Graphite.
- delocalised electrons form weak bonds between layers.
- can conduct electricity as these electrons can move
- layers slide past each other
What is an allotrope?
A structure made of the same element but arranged differently.
What are fullerenes?
They are used for electronics, composites and medical purposes.
What is the size of a nanoparticle?
100-2500nm
What is the size of a coarse particle?
bigger than 2500nm
Why are fullerenes useful?
They have a high surface area to volume ratio so fewer are needed for purpose. Double the length = half the ratio.
