Video Transcript
At room temperature and pressure,
the most stable form of sulfur is the simple molecule S8. However, heating the material to a
high temperature can produce continuous chains of sulfur atoms. Which term best describes the type
of structure displayed by high-temperature sulfur? (A) Ionic, (B) simple molecular,
(C) giant covalent, (D) metallic, or (E) atomic.
This question is asking about the
type of structure displayed by high-temperature sulfur. While they acknowledge that sulfur
can form simple molecules, the high-temperature version that they’re talking about
involves continuous chains of sulfur atoms. The key words here are “continuous
chains.” Which of these five choices
describes the structure with continuous chains of atoms bonded together? That’s choice (C), giant covalent
structures.
Giant covalent structures involve
continuous networks of covalent bonds, exactly what they are describing in the
question. To be thorough, let’s eliminate the
other choices from consideration as well.
It’s worth noting that sulfur on
the right-hand side of the periodic table is a nonmetal, as it forms a sulfur two
minus ion. This allows us to eliminate both
ionic and metallic from consideration. In the case of metallic, sulfur is
a nonmetal, so it can’t form metallic bonds. In the case of ionic, while sulfur
can form ionic compounds, there is no metal to provide a positive ion to form the
other half of the ionic bond in this situation.
It is not a simple molecular
structure, either, because simple molecular structures are not continuous. Continuous implies that the chains
go on and on with an indefinite size, whereas simple molecules have a definite
size. Lastly, atomic structure is too
general of a term to best to describe the structure displayed here. While we could describe the giant
covalent network described here as an atomic structure, we could also describe all
chemical compounds as atomic structures. So, it’s not a narrow enough term
to specifically describe the structure displayed here.
In the end, the key piece of
information to recognize is that a continuous chain of atoms suggest a giant
covalent structure. Note that giant covalent and
network covalent are different names for the same structure, and we can use them
interchangeably.
So, which term best describes the
type of structure displayed by high-temperature sulfur? That’s a giant covalent
structure.
