b) LiH (s) + H₂O (l) --> LiOH (aq) + H₂ (g)
When an alkali metal reacts with water it always produces the metal hydroxide and hydrogen gas which is liberated into the air.
2M(s)+2H₂O (l) →2MOH (aq)+ H₂ (g)
Lithium reacts with water very vigorously.
Alkali metals need to be stored under oil to prevent them from reacting with the oxygen and water vapour in the air. The reactivity of the alkali metals increases down the group.
Alkali metals consist of the following metals:
Lithium, sodium, potassium, rubidium, caesium.
Lithium, sodium and potassium also react vigorously with water and produce hydrogen gas and which is liberated in the air.
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