Question

the atomic size of sodium is more than that of aluminium
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Answer 1

Answer:

Due to the addition of electrons in the same shell in Aluminum, the nuclear charge on Aluminium is more than that of Na and thus the atom tends to shrink a little in size. Hence, Al has a smaller atomic size than Na. Aluminium (13) and Sodium (11) come in the same period, i.e, the 3rd period.

Answer 2

Explanation:

Due to the addition of electrons in the same shell in Aluminum, the nuclear charge on Aluminium is more than that of Na and thus the atom tends to shrink a little in size. Hence, Al has a smaller atomic size than Na. Aluminium (13) and Sodium (11) come in the same period, i.e, the 3rd period.