Answer :
Final answer:
The electron configuration of magnesium (atomic number 12) is 1s² 2s² 2p¶ 3s², which is often abbreviated as [Ne]3s². As an alkaline earth metal, it fills the 3s orbital with its last two electrons, following the 'building-up' principle. The most common isotope of magnesium has 12 neutrons, in addition to its 12 protons and electrons.
Explanation:
The electron configuration of magnesium, which has an atomic number of 12, follows the principle of building up from lower to higher energy levels. Magnesium's 12 electrons are arranged as follows:
The first two electrons will fill the 1s orbital, giving us 1s2.
The next two electrons will fill the 2s orbital, resulting in 2s2.
The remaining six electrons will fill the 2p orbitals, giving 2p6.
The last two electrons go into the 3s orbital, completing the configuration with 3s2.
Therefore, the complete electron configuration for magnesium is 1s2 2s2 2p6 3s2. This is sometimes represented in a shortened form as [Ne]3s² to indicate that magnesium has the same electron configuration as neon plus two additional electrons in the 3s orbital.
Addressing the statement about magnesium's atomic composition, a neutral magnesium atom indeed has 12 protons and 12 electrons. The number of neutrons in magnesium can vary because magnesium has isotopes, but the most common isotope of magnesium has 12 neutrons, making the statement (a) that it has 12 protons, 12 electrons, and 12 neutrons true for this isotope.
