chemistry topic 2 Flashcards
why are the three types of strong chemical bonds
- Ionic
- Covalent
- Metallic
describe ionic bonding
Particles are oppositely charged ions
Between metals and non-metals
describe covalent bonding
Particles are atoms which share pairs of electrons
describe metallic bonding
Particles are atoms which share delocalised electrons
In metallic elements
and alloys
what happens during ionic bonding
- Between a metal and non-metal
- Metals LOSE electrons to form a
POSITIVE charge - Non-metals GAIN electrons to form a
NEGATIVE charge
what is an ionic compound composed of
An ionic compound composed of positive
ions (cations) and negative ions (anions).
what is Electrostatic Attraction
When oppositely charged ions are
attracted to each other
what is made during electrostatic attraction
ionic bonds
describe why things have a high melting point.
- Giant 3D ionic lattice
- there are strong electrostatic forces of attraction between oppositely charged ions
- so large amounts of energy are needed to break the bonds
why are solid ionic compounds not conductive
When solid, the ions cannot move so do not conduct electricity.
why are molten/disloved ionic compounds conductive
When molten or dissolved in water, ions
are free to move and carry charge so
conduct electricity.
when does covalent bonding occur
Covalent bonding occurs between a non-metal and a non-metal. Atoms share outer
shell electrons with each other
what is it called if Two pairs of electrons are shared between atoms
double bond
what happens when you apply heat to molecules close together
intermolecular forces of attraction are easily broken and the structure is lost
how are molecules attracted to eachother
Molecules are attracted to each other by
intermolecular forces