Question

In between na+, mg2+ and al3+ whose size is more and why ?

Answer 1

Na+>Mg2+>Al3+
Because,
In Na+ => No. of protons=11, No. of electrons=10
In Mg2+ => No. of protons=12, No. of electrons=10
In Al3+ => No. of protons=13, No. of electrons=10

So, as no. of electrons for all 3 are same then the atom with more no. of protons will provide more attractive force so small size
Hence, Na+ is the largest among the 3

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