4.2.2 How bonding and structure are related to the properties of substances

Question 1

State properties of ionic substances

Answer 1

• High melting and boiling point (strong electrostatic forces between oppositely charged ions)
• Do not conduct electricity when solid (ions in fixed positions)
• Conduct when molten or dissolved in water - ions are free to move

Question 2

Describe the structure and properties of simple molecular covalent substances

Answer 2

• Do not conduct electricity (no ions)
• Small molecules
• Weak intermolecular forces, therefore; low melting and boiling points

Question 3

Describe properties of metals.

Answer 3

• High melting/boiling points (strong forces of attraction)
• Good conductors
  of heat and electricity (delocalised electrons)
• Malleable, soft (layers of atoms can slide over eachother whilst maintaining the attraction forces)

Question 4

How do intermolecular forces change as the mass/size of the molecule increases?

Answer 4

They increase. That causes the melting/boiling points to increase as well (more energy needed to overcome these forces).

Question 5

What is the formula of sodium chloride?

Answer 5

NaCl

Question 6

What are the 3 states of matter?

Answer 6

• Liquid
• Solid
• Gas

Question 7

What do these state symbols stand for:
(s), (g), (l), (aq)

Answer 7

• Solid
• Gas
• Liquid
• Aqeous