The element magnesium has 2 valence electrons. what is the most likely charge on a magnesium ion? a) 2+ b) 2- c) 6- d) 6+

A) 2+

Explanation: Magnesium is an element with atomic number 12 and thus contain 12 electrons. It is a s block element as the last electron enters the s orbital. The nearest noble gas is Neon with 10 electrons.

The electrons are filled according to Afbau's rule in order of increasing energies and thus the electronic configuration is:

Thus Magnesium loses two valence electrons so as to attain stable configuration and forms a ion with noble gas configuration.