Q. 9. has completely filled and shells. Explain.
The atomic number of Na = 11
No. of electrons in Na atom = 11
In ,the positive charge is obtained due to the loss of one electron from M shell of Na atom.
So, No. of electrons in Na+ ion = 11 -1 = 10
Hence, electronic configuration of Na+ = 2, 8
In Na+, K and L shells are completely filled since K shell can have a maximum of 2 electrons and L shell can have a maximum of 8 electrons.
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