Ethylene oxide (oxirane) as shown by the chemical structure below is an important molecule used as a precursor to several other compounds. Instead of having two carbon atoms and one oxygen atom in a row, the three atoms form a ring. It was used in World War I to produce the coolant ethylene glycol and for the production of mustard gas (a chemical weapon). How does the structure of ethylene oxide differ from the structure of ethanol?

• A. Oxirane has two H atoms less than ethanol and has a different skeletal structure.
• B. Oxirane and ethanol are isomers of each other.
• C. Oxirane has one H atom less than ethanol but the skeletal structure is the same.
• D. There is no different among the two molecules.

Answer: (A)