Answer:
The first shell, n=1, can hold up to 2 electrons, so 2 of the 12 electrons in magnesium will occupy the first shell. This leaves 12−2=10 electrons to place. The second shell can hold up to 8 electrons, so 8 of the remaining electrons will be in the n=2 level and the 2 remaining electrons will be in the third level.
Explanation:
