2- Structures, properties and uses part 2 Flashcards
Covalent:
Why is graphite slippery?
It’s layers have weak intermolecular forces causing them to slide of each other easily
Covalent:
Why is diamond (and silica) hard?
Their carbon atoms are covalently bonded to four other carbon atoms
Why is graphite a conductor?
It’s delocalised electron is a charged particle
Ionic:
What holds ionic structures together?
Electrostatic forces
Ionic:
Why do ionic compounds have high melting and boiling points?
A lot of energy is needed to overcome the ionic bonds
Ionic:
Why are ionic compounds in liquid form conductors of electricity?
The ions are free to move
Features of simple covalent molecules?
Low melting and boiling points
Do not conduct (no overall charge)
What are intermolecular forces?
The forces of attraction between molecules
Melting and boiling points of molecules
Large have high because of strong intermolecular forces (attractions)
Small have low because of weak intermolecular forces (attractions)
Metallic:
Why can metals be made into wires?
They can move into a new position without breaking apart
Metallic:
What are alloys?
Mixtures of metals or metals mixed with other elements
Metallic:
What are shape memory alloys?
Can be bent or deformed into shapes, when heated they return to original shape
Metallic:
Why are metals conductors?
There delocalised electron can move throughout the lattice and transfer energy quickly
What is a giant ionic lattice?
A 3D structure of oppositely charged ions bonded ionically, eg. Table salt (sodium chloride)
Ionic:
What charge do ionic compounds have?
No charge
