Chemistry, 4.1- Atomic Structure and the Periodic Table

Suggest two reasons why Mendeleev’s periodic table is accepted by other scientists.
[2 marks]

• Properties match Mendeleev’s prediction.

• Element fitted in the gap which left by him.

Look at the element in group 7 in periodic table.
Explain why chlorine is less reactive than fluorine. [4 marks]

• Chlorine has grater distance between nucleus and outer electron.

• Chlorine has greater shielding of outer electron.

• Chlorine has less attraction between outer electron and nucleus.

• Chlorine gain electron less easily.

This is a displacement reaction.

Sodium bromide + fluorine → _____ + _____

State the product.
Give your reason.[2 marks]

Sodium fluoride and bromide.
(Because) fluorine is more reactive than bromide.

This is when sodium reacts with water.

Complete the balanced equation. [4 marks]

___Li + ___H₂O → _______ + ______

2Li + 2H₂O → 2LiOH + H₂

Explain why reactivity change when going down group 1.

• Greater distance between nucleus and the outer electron.

• Less attraction.

• Outer electron loss more easily.

• Reactivity increase.

Explain why group 0 element is not reactive. [2 marks]

• Full outer energy level.

• Stable.

Describe the trend of boiling point when going down group 0 in the periodic table. [1 mark]

• Increase.

Compare the properties with transition metal with group 1 element. [3 marks]

• Transition metal is harder.

• Transition metal is denser.

• Transition metal is less reactive.