Video Transcript
The table below shows how various
nonmetals react with oxygen. Using the results in the table,
what is the order of reactivity of the elements from most to least active?
Nonmetals are primarily found on
the right-hand side of the periodic table. All of the elements in the table
are nonmetals. When these elements react with
oxygen, an oxide is formed. An oxide is a chemical compound
that contains at least one oxygen atom bound to another element. The element that is not oxygen in
an oxide compound can be a metal or a nonmetal.
We will focus on only the oxides
formed with the nonmetals phosphorus, chlorine, sulfur, and carbon in this
question. We want to rank the four nonmetals
according to their activity with oxygen when forming their oxides. We want to use the descriptions of
their reactions in air presented in the table to do so.
Phosphorus bursts into spitting
flames when exposed to air without any heating. Gaseous diphosphorus pentoxide is
produced in this violent reaction. We can deduce that phosphorus is
the most active of these four elements.
Chlorine, while a very reactive
element with many other elements, does not react readily when exposed to oxygen. So we can deduce that this is the
least active of the four elements with oxygen.
Sulfur burns when heated over a
Bunsen burner. This produces toxic sulfur
oxides. Since this does not happen
spontaneously and requires some heat, sulfur is not as active as phosphorus in
oxygen. But sulfur is more active than
carbon.
Carbon must be heated until red
hot, which takes some time. Once carbon is adequately heated,
it can be added to pure oxygen. At this point, it will react to
produce the carbon oxides. Thus, carbon is less active in
oxygen than sulfur as it requires not only a lot of heat, but concentrated
oxygen.
Phosphorus is the element with the
highest activity with oxygen, with sulfur next, followed by carbon, and finally the
least active is chlorine. Therefore, using the results in the
table, the reactivity of the elements from most to least active is P, S, C, and
Cl.