(a) How does the atomic size vary on going down from top to bottom in a group of the periodic table? Why does it vary this way?
(b) Lithium, sodium and potassium are all metals that react with water to liberate hydrogen gas. Is there any similarity in the atoms of these elements? Explain your answer.

(a) The atomic size increases on going down the group of the periodic table as on moving top to the bottom, shells are added at each step due to this the size of the atom increases.

(b) Yes, the atoms of all the three elements lithium, sodium, and potassium have one electron in their outermost shells. Therefore, they react with water to liberate hydrogen gas.


Simply Easy Learning

Updated on: 10-Oct-2022


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