Group 1 - Alkali Metals

Question 1

What are the ‘alkali metals’?

Answer 1

Question 2

List some properties of the alkali metals.

Answer 2

• Very soft / easy to cut
• Have relatively low melting points and boiling points
• Very reactive

Question 3

Describe the trend in reactivity for the alkali metals.

Answer 3

The reactivity of the metals increases as you go down the group

Question 4

Explain the trend in reactivity for the alkali metals.

Answer 4

• Reactivity increases as you go down group
• Outer electron is more easily lost because the atomic radius increases as you go down group
• Less strongly attracted to nucleus, less energy needed to remove it

Question 5

(Exam-style question)

Potassium and caesium are in the same group of the periodic table.

Explain, in terms of electrons, why potassium and caesium are in the same group.

Answer 5

• They each have 1 electron in their outer shell
• They are both in group 1

Question 6

Describe what you would expect to see when lithium reacts with water.

Answer 6

Lithium would move around surface of the water, fizzing vigorously, then dissolve

Question 7

Describe what you would expect to see when sodium reacts with water.

Answer 7

• Sodium would move around surface of the water, fizzing vigorously
• It would decrease in size as it melts and dissolves

Question 8

Describe what you would expect to see when potassium reacts with water.

Answer 8

• Potassium would move around surface of the water, fizzing vigorously
• It would decrease in size as it melts and dissolves
• The potassium would become hot enough for the hydrogen gas produced by the reaction to ignite

Question 9

Considering the reactivity trend for the alkali metals, predict how rubidium and caesium will react with water.

Answer 9

They will react much more violently with water