Question

which neutral atom has the same number of electron as o-2 ions​

Answer 1

Explanation:

Ar has the same number of electrons as Ca

2+

. These are isoelectronic species.

The atomic number of Ar is 18. It contains 18 electrons. The atomic number of Ca is 20. It contains 20 electrons.

It loses 2 electrons to form Ca

2+

ion with 18 electrons.

Answer 2

Answer:

Argon....................