Q5 of 40 Page 130

Ca2+ has completely filled outer shell. Justify your answer.

Ca2+ means that calcium has lost 2 electrons.

Now; atomic number of Ca = 20


Since, it has lost 2 electrons, thus the no of electrons left are = 18


Thus, atomic configuration of Ca2+ = 2, 8, 8


This shows that the Ca2+ has a completely filled outer shell.


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