Group 1 - Alkali Metals Flashcards
Why do alkali metals become dull?
They react with oxygen in the air
Properties of alkali metals (4)
Very reactive metals
Low density (soft)
Shiny+grey
Stored under oil - they react with oxygen and water vapour in air
What happens when lithium reacts with water?
Floats on surface
Fizzes
Moves around slowly
What happens when sodium reacts with water?
Moves faster
More reactive than lithium
Melts
What happens when potassium reacts with water?
Very reactive
Burns as soon as it comes into contacts with water
When sodium and water react what do they make?
Sodium hydroxide and hydrogen
When potassium and water react what do they make?
Potassium hydroxide and hydrogen
Why do all group 1 elements have similar properties?
They all have 1 electron in the outer shell
What happens when group 1 elements react?
They lose one electron - outer shell is full (more stable)
Why is a positive ion formed when group 1 elements react?
The number of protons is one more than the number of electrons
What is losing an electron described as?
Oxidation reaction
Why is potassium more reactive than sodium?
The electron it loses from the outer shell is further from the nucleus so it is easier to lose it
What happens in a flame test?
- Bunsen burner on blue flame
- Dip no chrome wire in hydrochloric acid - cleans it
- Dip back in acid then in powder
- Hold over flame
If lithium compounds are present what colour will the flame be?
Red flame
If sodium compounds are present what colour will the flame be?
Orange flame
