Which element shares the most characteristics with sodium (na)? a. magnesium (mg) b. neon (ne) c. potassium (k) d. argon (ar)

The answer is potassium (K).

Potassium (K) shares the most characteristics with sodium (Na)

Explanation:

Valencia electrons are the electrons found in the last electronic layer (called valence orbitals). These electrons are what determine the ability of the atom to form bonds. When an element joins another, it does so through its valence electrons. It is also possible to say that these electrons are the electrons furthest from the nucleus of the atom, which is why they participate in chemical reactions.

And electrons, in addition to determining the reactivity of the elements, allows to determine their location in the Periodic Table. All elements of the same group have the same number of valence electrons (This does not occur in transition metals). The valence electrons increase in number as one advances in a period. Then, at the beginning of the new period, the number decreases to one and begins to increase again.

In the periodic table the elements are arranged so that those with similar chemical properties are located close to each other.  

The columns of the table are called groups. There are eighteen groups, numbered from number 1 to 18. In the same group, the chemical properties are very similar because, as mentioned, they have the same number of electrons located in the last energy level.

Potassium (K) and sodium (Na) belong to the same group, so they will share most of the characteristics.

it is stable as it is in group 0 which have full outer shells of electrons