Periodicity

Question 1

State the trend in the solubility of the hydroxides of the group II metals.

Answer 1

Increases down group II.

Question 2

State the trend in the solubility of the sulphates of the group II metals.

Answer 2

Decreases down group II.

Question 3

State the trend in reactivity of haloalkanes.

Answer 3

Increases down group VII

Question 4

What is observed when sodium reacts with oxygen?

What is the oxide formed?

Answer 4

Yellow flame

White solid formed

Na₂O

Question 5

What is observed when magnesium reacts with oxygen?

What is the oxide formed?

Answer 5

Bright white flame

White fumes

White solid formed

MgO

Question 6

What is observed when aluminium reacts with oxygen?

What is the oxide formed?

Answer 6

Bright white flame

White solid

Al₂O₃

Question 7

What is observed when silicon reacts with oxygen?

What is the oxide formed?

Answer 7

White solid

SO₂

Question 8

What is observed when phosphorus reacts with oxygen?

What is the oxide formed?

Answer 8

White flame

White fumes

P₄O₁₀

Question 9

What is observed when sulphur reactions with oxygen?

What is the oxide formed?

Answer 9

Blue flame

Fumes

SO₂ and some SO₃

Question 10

Why does Na₂O form an alkaline solution when it reacts with water?

Answer 10

The O^2- ion reacts with the water:

O^2- + H₂O → 2OH^-

Question 11

How does aluminium oxide reaction with:

1. Acids
2. Bases

Answer 11

Acids:

Al₂O₃ + 6H⁺ → 2Al³⁺ + 3H₂O

Bases:

Al₂O₃ + 2OH^- + 3H₂O → 2[Al(OH)₄]^-