Bonding Flashcards
What are ionic, covalent, and metallic bonding?
Ionic bonding involves the electrostatic attraction between oppositely charged ions in a lattice. A single covalent bond contains a shared pair of electrons. Metallic bonding involves attraction between delocalized electrons and positive ions arranged in a lattice.
Name the 4 crystal structures and an example for each one:
- Ionic: NaCl
- Metallic: Mg
- Macromolecular: Diamond
- Molecular: I2
Why do giant ionic lattices conduct electricity when molten or in solution?
The ions are free to move around and carry charge.
Why does Mg have a higher melting point than Na if they both have metallic structures?
Mg forms Mg2+ ions, whilst Na forms Na+ ions. Therefore there is a higher electrostatic attraction between the delocalised electrons and Mg2+ ions. Furthermore, there are more delocalised electrons. The higher electrostatic attraction therefore more energy is required to break bonds therefore a higher melting point.
What are coordinate covalent bonds?
Where one atom donates two electrons to form a covalent bond.
Why is graphite very slippery and also conducts electricity?
Graphite is arranged in layers with weak VDW forces between them meaning it is easy for the layers to slide over each other. Each carbon atom is covalently bonded to 3 other carbons therefore the 4th carbon is delocalized and therefore can carry a charge.
What symbol should we use for coordinate bonds?
An arrow.
Why are metals, good thermal conductors?
The delocalised electrons can transfer kinetic energy.
Why are metals malleable and ductile?
Metal’s layers of ions can slide over each other, but are still held together by the delocalised electrons.