IGCSE Edexcel- Chemistry: Bonding

Question 1

Ionic bonding

Answer 1

Definition: Electrostatic forces of attraction between oppositely charged ions (giant ionic lattice)

Composed of: +ve metal, -ve non metal

High mp/bp: strong electrostatic forces of attraction that require alot of energy to break apart. The greater the ionic charge, the greater hte attraction between oppositely charged ions.

Brittle: shatter when struck by a force

Conduct (aq): Ions in fixed lattice, not free to move. Once melted, lattice has broken down, ions are free to move.

Question 2

Covalent bonding

Answer 2

Definition: Electrostatic force of attraction between shared pair(s) of electrons and nuclei

Composed of: non metal and non metal

Simple molecular: weak intermolecular forces dont require much energy to break

Giant covalent: strong covalent bonds between all atoms, requires alot of energy to break

Question 3

Metallic bonding

Answer 3

Definition: Strong electrostatic forces of attraction between +ve metallic ions and -ve electrons

Composed of: same metal + same metal Giant structure of +ve ions closely packed in a regular arrangement (lattice), surrounded by a sea of delocalized electrons.

High mp/bp: strong electrostatic forces of attraction between +ve metal ions and -ve delocalized electrons requires a lot of energy to break

Good electrical conductors: delocalized electrons free to move and carry charge.

Malleable: +ve metal ions slide over each other, delocalized electrons move to minimize repulsion forces

Question 4

Alloys

Answer 4

Definition: mixture of two or more metals or a metal and non metal

Harder: Different sized atoms disrupts regular arrangement, making it more difficult for +ve ions to slide