C3. Structure And Bonding Flashcards
1
Q
How do solids turn into liquids?
A
- at its melting point
- temperature increases and particles vibrate faster
- at melting point enough energy is transferred and forces particles to break
- particles break away from fixed positions and start to move around
2
Q
How do liquids turn into gases?
A
- at boiling point
- temperature increases and particles move faster
- more energy is transferred and some particles can escape from surface before boiling point
- at boiling point, bubbles of gas form within liquid and rise freely to surface
3
Q
What do elements from when they react?
A
They form compounds by gaining, losing or sharing electrons
4
Q
When are ionic compounds formed?
A
When metals react with non metals
5
Q
Explain ionic bonding
A
Ionic compounds are held together by strong forces of attraction between their oppositely charged ions
6
Q
Why does it take a lot of energy to break a giant ionic structure?
A
- there are many strong bonds that operate in all directions and hold the giant ionic lattice together
7
Q
When are covalent bonds formed?
A
When atoms of non metal share pairs of electrons with each other. Each shared pair of electrons is a covalent bond
8
Q
Simple molecules…
A
- low melting and boiling points
- forces are weak
- no overall charge, cannot conduct electricity
9
Q
Fullerenes…
A
- carbon
- structure is based on hexagonal rings of carbon atoms (cages or tubes)
- used to transport drugs in body
10
Q
Graphene…
A
- single layer of graphite (1 atom thick)
- excellent electrical conductor
11
Q
Metallic bonding…
A
- atoms are closely packed together in regular layers
- positive charged metal ions held together by electrons from outermost shell of each atom
- delocalised electrons are free to move throughout giant metallic lattice
