Group 1 (Alkali Metals)

Question 1

How many electrons do they all have in their outer shell and what does having the same number of electrons mean?

Answer 1

They have 1 electron in their outer shell, and since they all have this same number of electrons, they share similar properties

Question 2

What is produced when a group 1 metal reacts with water?

Answer 2

• The hydroxide of that metal and hydrogen
• The solution is always alkaline

Question 3

What happens to reactivity as you descend the group?

Answer 3

It increases

Question 4

What is the reaction of lithium with water like?

Answer 4

• Slow
• It does not produce enough heat to allow it to melt

Question 5

What is the reaction of sodium with water like?

Answer 5

• Faster than lithium
• Enough heat is produced for it to melt
• Hydrogen released catches fire

Question 6

What is the reaction of potassium with water like?

Answer 6

• It reacts violently
• Hydrogen released burns with a lilac coloured flame
• The potassium melts into a shiny ball

Question 7

What happens when you react a group 1 metal with oxygen?

Answer 7

• They form metal oxides, and the metals tarnish, with a dull coating forming which covers the metals
• The reactions, again, get more violent as you move down the group

Question 8

What are the physical properties of group 1 metals?

Answer 8

• They have low melting points which decrease as you move down the group. This is because the electron gets further from the nucleus
• They have low densities, with densities increasing as you move down the group
• They are soft and easy to cut, getting softer as you move down the group

Question 9

What can you predict for rubidium based on the properties of potassium?

Answer 9

• It would react more violently with water and oxygen, because it is further down the group
• It would have a lower melting point
• It would be softer
• It would be denser

Question 10

In terms of electronic configuration, why does the reactivity of group 1 metals increase as you move down the group?

Answer 10

• As you move down the group, the period number increases meaning the number of electron shells increases
• This means that the 1 outermost electron gets further and further from the nucleus, resulting in much weaker forces of attraction between the electron and the nucleus
• This leads to increased reactivity as less energy is needed and the electron is lost more easily

Question 11

What are the elements in group 1 called?

Answer 11

Alkali metals