The elements sodium, magnesium, and silicon
A)are in the same period of elements.
B)have the same number of neutrons.
C)have the same mass number.
D)are isotopes of each other.
E)are in the same group.

Question

Quizplus · Accepted Answer

Sodium (Na), magnesium (Mg), and silicon (Si) are all in the same period of the periodic table, specifically period 3, indicating they have the same number of electron shells.

The Elements Sodium, Magnesium, and Silicon