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Group 1: Alkali Metals
Chemistry
Periodic Table
lithium, sodium, potassium, rubidium, caesium and francium
Properties
Form alkaline solutions when they react with water
Share similar properties - have one electron in their outermost shell - such as…
• Very reactive (only need to lose 1 electron to become stable)
• Soft and easy to cut - get softer down the group
• The first three are less dense than water – they float!
• Have low melting points that get lower down the group
Group 1 metals get more reactive down the group
Easier to lose its outer electron to form 1+ ions
The next shell down is already full – stable arrangement!
Down Grp 1, the number of electron shells increases…
• Outer electron gets further away from the nucleus - weaker forces of attraction between the outer electron and the positive nucleus
• Less energy is needed to overcome the force of attraction - gets weaker so electron is lost more easily
• So, they get more reactive as you go down the group
Use electronic configuration to support your answers in exams.
Reactions
Alkali metals are stored in oil to stop them from reacting with oxygen & water
Reactions with Water
With oxygen...
With chlorine...
Links
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