Answer:
Sulfur (but not argon or sodium.)
Explanation:
In an ionic bond, one atom would completely lose one or more electrons while the other atom would completely gain those electrons.
For that to happen, the first atom needs a strong tendency of losing electrons. The second atom needs a strong tendency of gaining electrons.
Atoms of metals tend to lose electrons. On the other hand, atoms of nonmetals tend to gain electrons.
Alkaline earth metals (IUPAC group [tex]2[/tex]) include elements such as magnesium and calcium. Like many other metals, alkaline earth metal atoms tend to lose electrons. Atoms of elements that form ionic bonds with alkaline earth metal atoms should tend to accept electrons.
Among the choices for the other element in this ionic bond:
- Sodium is an alkaline metal.
- Sulfur is an IUPAC group [tex]6[/tex] non-metal.
- Argon is a noble gas.
Because sodium is a metal, it is unlikely that sodium would accept electrons from alkaline earth metal elements. Rather, sodium might form an alloy (with metallic bonds rather than ionic bonds) when melted and mixed with alkaline earth metals.
Sulfur is a non-metal and is right under oxygen in group [tex]6[/tex] of the periodic table. Like atoms of other nonmetals in that group, sulfur atoms tend to gain electrons and could readily form ionic bonds when mixed with alkaline earth metal elements.
Argon is a noble gas. Noble gas elements are considerably chemically inert. They seldom react with other elements. Even if they do so, they tend to form covalent bonds rather than ionic bonds. In practice, alkaline earth metals such as calcium may even be stored in containers filled with argon to prevent the metal from reacting with oxygen in the air.
