Give the symbol for the cation possessing a positive two charge that is isoelectronic with neon.

Explanation:

Magnesium is the element of group 2 and third period. The atomic number of Magnesium is 12 and the symbol of the element is Mg.

The electronic configuration of the element Magnesium is:-

Noble gas notation includes a shorthand way of writing the electronic configuration of the elements.

The nearest noble gas - Neon which has electronic configuration of -

So, the noble gas notation for Magnesium is:-

Thus, Magnesium losing 2 electrons will be isoelectronic with neon and has configuration of .

Thus, the symbol of the cation is:-