Question

Lithium, sodium, potassium are all metals that react with water to liberate hydrogen gas. Is there any similarity in the atoms of these elements?

Answer 1

Yes there are some similarity in the atoms of these elements-

All of these are metals.
All of them react with water to form alkalis and hydrogen gas.
All of them have a valency of 1.
They all lie in same group (that is Group 1) in Modern Periodic Table.

All of them have same no. of valence electrons. which is the reason for their similar chemical properties.

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