Question

When a sulfur (s) atom becomes an ion, what charge does it usually have?

Answer 1

Chemical elements have the electrons in their orbitals and try to attain inert or noble gas configurations to get stability. As the noble gases have completely filled electrons in their orbitals. Sulfur tries to gain two electrons, as it attains argon electronic configuration to get stability.

Complete answer:
Periodic table is the representation of chemical elements arranged in the order of increasing atomic numbers in vertical columns and horizontal rows. The vertical columns are called groups and the horizontal rows are called periods. There are $7$ periods and $18$ groups.
The elements belonging to group $16$ are called oxygen family or pnicogens.
Sulphur is the element with atomic number $16$ and belongs to the oxygen family. The electronic configuration of sulphur is $\left( {Ne} \right)3{s^2}3{p^4}$, which means sulphur has six electrons in its outermost shell.
Thus, Sulphur tries to gain two electrons to attain the nearest noble gas configuration. The noble or inert gases are stable due to the presence of completely or fulfilled electrons in their shells or orbitals. The nearest noble gas to sulphur is Argon, it has atomic number $18$.

Thus, sulphur when turned into ion it carries the charge of $- 2$, as sulphur usually gains two electrons to get stability.

Note:
The atom or chemical element tries to gain or lose electrons to attain the nearest noble gas configuration, the element belonging to the oxygen family tries to gain two electrons. Thus, the elements of the oxygen family usually carry a charge of $- 2$.