The elements in group 1 are known as the alkali metals
Alkali metals have one electron in their outermost shell
Alkali metals have lowmelting and boiling points that decrease down the group
Alkali metals become more reactive down the group
Why do alkali metals become more reactive down the group?
The 1 electron on their outer shell gets further away from the influence of the nucleus as you go down the group - this means it can be lost more easily
Why are alkali metals stored under oil?
Because they react vigorously with oxygen and water , including moisture in the air
Group 1 metals react with oxygen to form metal oxides - for example sodium reacts with oxygen to form sodium oxide (Na₂O)
Alkali metals react with water to produce a metal hydroxide and hydrogen gas
Potassium + water --> potassium hydroxide + hydrogen
Group 1 metals have a low density
Why are Lithium, Potassium and Sodium the only alkali metals that float on top of water?
Because they are less dense than water
When a metal hydroxide is dissolved in water , an alkaline solution is produced
Alkali metals react with non metals to form ionic compounds - When this happens, the metal atom loses one electron to form a metal ion with positive charge (+1)
