How Many Electrons Are Gained/lost By Magnesium And What Is The Charge On The Ion That It Forms?

Magnesium is a group 2 metal. Metals are those elements that lose electrons. Whenever an element loses an electron, it gains a positive charge. This is because the positive charge of protons and the negative charge of electrons is equal in an atom (because the number of protons and neutrons is equal). Therefore, the net charge on the atom is zero. Now, when any number of electrons is removed from the atom, there is a charge imbalance and the positive charge comes to dominate. That is why the net charge on the ion becomes positive. Positive ions are known as cations.

Being in Group II, Magnesium loses 2 electrons to form a positive ion.
The formula for the Magnesium ion is:
Mg²⁺
(Two electrons are lost, therefore, the charge is double positive)

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