Topic 2 - Bonding And Structure Flashcards
(17 cards)
What is metallic bonding
Attraction between positive metal ions and delocalized elections
Ionic bonding
Attractions between oppositely charged ions (one positive and one negative ion)
Covalent bonding
The sharing of elections to gain a full outer shell
Why do ionic compounds have a high melting point
They have strong ionic bonds, which require a lot of energy to overcome
What do you need to be able to conduct electricity
Electrons or ions that are free to move
Why can metals conduct electricity
They have delocalized elections
The electrons can carry charge throughout the structure
Why can’t solid ionic compounds conduct?
The ions are not free to move
When can ionic compounds conduct electricity? And why?
When they are molten or dissolved in water. Because the ions are then free to move.
What type elements form ionic compounds
A metal and a non metal
What type of compounds can form covalent bonds?
Nonmetals
What is the name of the forces that hold covalent molecules together
Intermolecular forces
Are intermolecular forces strong or weak? How does this affect the boiling point?
They are very weak. They require very little energy to overcome
Why does diamond have such a high melting point ?
- diamond is a giant covalent lattice
- a lot of energy is required to overcome the covalent bonds
Why can graphite conduct electricity?
- it has delocalised electrons that can carry charge are are free to move throughout the structure
Why is graphite soft
- it is made up of layers that can easily slide over one another
- there are no bonds between the layers
What is the special feature of nanotubes?
- they have a very high surface area to volume ratio
- ## the is because they are hollow
How do mental and nonmetals form ions
- the metal looses electrons to become a positively charged ion
- the non metals atoms gains electrons to become a negatively charged ion
