In basic chemistry, ozone (O3) is related to oxygen (O2) in which way? Ozone is an example of an ______ of oxygen.

Introduction / Context:
This question is about the relationship between ozone and ordinary oxygen in terms of chemical classification. Both ozone and dioxygen are forms of the same chemical element, oxygen, but they differ in molecular structure and properties. Understanding terms such as allotrope, isotope and isobar is important in basic chemistry when describing different forms of elements and nuclei.

Given Data / Assumptions:

• Ozone has the molecular formula O3 and ordinary oxygen has formula O2.
• Both substances are composed only of oxygen atoms.
• We are asked to fill in the blank in the statement that ozone is an example of an something of oxygen.
• The options include allotrope, isotope, isobar, isotone and coordination complex.

Concept / Approach:
Allotropes are different structural forms of the same chemical element in the same physical state. For example, diamond and graphite are allotropes of carbon, and O2 and O3 are allotropes of oxygen. Isotopes are atoms of the same element with different numbers of neutrons but the same number of protons, which is a nuclear property rather than a molecular structure property. Isobars and isotones are also nuclear concepts, not used for molecules in this way. Therefore, the correct classification of ozone with respect to oxygen is that it is an allotrope of oxygen.

Step-by-Step Solution:

Verification / Alternative check:
Chemistry textbooks list common allotropes such as diamond and graphite for carbon, white phosphorus and red phosphorus for phosphorus, and dioxygen and ozone for oxygen. Ozone is often described as a triatomic allotrope of oxygen. Isotope examples, such as oxygen 16 and oxygen 18, involve different mass numbers while still forming O2 molecules. This shows that the concept of allotropy, not isotopy, is used to describe the O2 and O3 relationship. These standard references confirm that allotrope is the correct term here.

Why Other Options Are Wrong:

• Isotope: Isotopes refer to atoms of the same element with different numbers of neutrons, not different molecular forms like O2 and O3.
• Isobar: Isobars are nuclei of different elements that have the same mass number, again not relevant for O2 and O3.
• Isotone: Isotones have the same number of neutrons but different atomic numbers, a nuclear property unrelated to this question.
• Coordination complex: Ozone is not a coordination compound; it is a simple molecule composed of three oxygen atoms.

Common Pitfalls:
Students sometimes confuse allotropes with isotopes because both terms involve different forms of the same element. The key difference is that isotopes relate to nuclear composition of single atoms, while allotropes relate to different structural arrangements of atoms in molecules or crystals. Remember that O2 versus O3 is a structural difference at the molecular level, so allotrope is the appropriate term.

Final Answer:
Ozone is an Allotrope of oxygen.