Bonding: Ionic Bonding

Question 1

Definition of Ionic Bonding

Answer 1

• Ionic bonding involves electrostatic attraction between oppositely charged ions in a lattice

Question 2

Compound Ions: Ammonium, carbonate, hydroxide, nitrate, sulfate, hydrogensulfate, phosphate

Answer 2

• Ammonium - NH4 +
• Carbonate - CO3 2-
• Hydroxide - OH -
• Nitrate - NO3 -
• Sulfate - SO4 2-
• Hydrogensulfate - HSO4 -
• Phosphate - PO4 3-

Question 3

Giant Ionic Lattices

Answer 3

• Ionic crystals are giant lattices of ions

• A lattice is a regular repeated three-dimensional arrangement of ions/molecules/atoms in a solid
• The structure is ‘giant’ because it’s made of the same basic unit repeated over and over again

Question 4

Properties of Ionic Compounds: Melting Point

Answer 4

• Ionic compounds have high melting points
• They have lots of strong electrostatic forces of attraction between oppositely charged ions
• These require a lot of energy to break

Question 5

Properties of Ionic Compounds: Electrical Conductivity

Answer 5

• As solids, ionic compounds cannot conduct heat/electricity because their ions are bonded together in the lattice and can’t move
• When liquid (molten) or in solution the ions can break free of the lattice and are able to move
• The ions are charged particles and so can carry heat and an electric current

Question 6

Properties of Ionic Compounds: Solubility

Answer 6

• Ionic compounds are usually soluble in water because water molecules are polar and have delta-positive/negative charges that can attract the ions away from the lattice, causing the compound to dissolve

Question 7

Factors which Affect the Strength of Ionic Bonds

Answer 7

• Charge on the ions
- The bigger the charge on the ion, the stronger the ionic bonding

• Size of the ions
- The smaller the ions, the stronger the ionic bonding