Chp 3

Question 1

What is the example for testing for evidence for the existence of ions?

3A

Answer 1

-Copper (II) Chromate (VI) solution
Aq copper (II) ions - Cu2+ - BLUE —> negative electrode
Aq chromate (VI) ions - CrO42- – YELLOW –> positive electrode

Question 2

How do we define the term polarising power?

3A

Answer 2

• Ability of a positive ion (catio) to distract the electron density of negative ion (anion)
• Ability of cation to attract an anion towards itself

Question 3

What are the 2 things that polarisation will be increased by?

3A

Answer 3

1. High charge + Small size of cation (high charge density of cation)
2. High charge + Large size of anion

Question 4

High charge + small size cation

3A

Answer 4

• Cation with large charge + small size –» LARGE POLARISING POWER

Question 5

High charge + large size of anion

3A

Answer 5

• Anion with large charge + large size –» more easily polarised

Question 6

Rules for polarisation w cations / anions?

Answer 6

• Cations cannot be polarised
• Large anions are easier to polarise

Question 7

What are the 4 types of lattices?

3E

Answer 7

• Giant metallic lattices
• Giant ionic lattices
• Giant covalent lattices
• Discrete (simple) molecular lattices