5.2 Ionic Bonding and Structure & 5.3 Covalent Bonding

Question 1

What is ionic bonding? Required.

Answer 1

• The electrostatic attraction between positive and negative ions

Question 2

What is an ionic lattice? Required.

Answer 2

• A repeating pattern of oppositely charged ions

Question 3

Why do ionic bonds result in the creation of a giant ionic lattice?

Answer 3

• Each ion attracts oppositely charged ions in all directions

Question 4

Describe the melting and boiling points of ionic compounds, and explain why they are like this.

Answer 4

• They have high melting and boiling points
• This is because large amounts of energy are needed to overcome the strong electrostatic attraction between the ions

Question 5

How do melting and boiling points differ across ionic compounds, and why?

Answer 5

• The melting and boiling points of lattices made of ions with greater ionic charges are higher
• This is because the ions are more strongly attracted together

Question 6

What type of solvents do ionic compounds dissolve in, and how?

Answer 6

• Polar solvents
• Water molecules are polar and break down the lattice and surround each ion

Question 7

Why does the solubility of ionic compounds differ?

Answer 7

• If the compound is made of ions with large charges, the ionic attraction may be too strong for the water molecules to break

Question 8

Do ionic compounds conduct electricity? Why/ why not?

Answer 8

• When in the liquid state or dissolved in water
• This is because in the solid state ions are in a fixed position in the giant ionic lattice, so solid ionic compounds are non-conductors of electricity
• When they are either liquid or aqueous, the solid ionic lattice breaks down and the ions are mobile, so in the liquid or aqueous state, an ionic compound is a conductor of electricity

Question 9

What is a covalent bond? Required.

Answer 9

• The strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms

Question 10

What is a dative covalent bond, and what can it also be known as?

Answer 10

• A covalent bond where the shared pair of electrons is supplied by one of the bonding atoms only (these electrons were originally a lone pair)
• Coordinate bond

Question 11

What is average bond enthalpy?

Answer 11

• A measurement of the strength of a covalent bond (the higher the value, the stronger the covalent bond)