3- Packing of Ions

Question 1

Ionic Bonding

Answer 1

Electrostatic attraction of oppositely charged ions.

STRONG: ELECTRON TRANSFER

e.g. Na+Cl- (Halite), Ca2+(F-)2 (Fluorite)

Question 2

Names of Ions

Answer 2

Cation - positive
Anion - negative

Formation of an ion is related to an energy required to be put into a system for ionisation to happen

Question 3

which become Anions and which cations?

Answer 3

Elements with high Electronegativity (EN) form anions

Elements with low Ionisation Potentials (IP) form cations

Question 4

What is considered to be a high difference in Electronegativity?

Answer 4

2 or more.

Question 5

Interionic distances

Answer 5

distance from nucleus to nucleus- can be determined using X-Ray Diffraction.

Only works if bonding is completely ionic

Question 6

Properties of Ionic Materials

Answer 6

• Moderate Hardness
• Multiple Perfect Cleavages
  (if a plate of ions in the structure is displaced, then electrostatic repulsion causes structure to shatter)
• High Symmetry