Kaplan Nursing Entrance Practice Exam

Which of the following is NOT an allotrope of carbon?

1. Diamonds

2. Graphite

3. Flourine

4. Buckminsterfullerene

The correct answer is: Flourine

The correct answer is Flourine because it is not an allotrope of carbon. Allotropes are different structural forms of the same element, where the atoms are bonded together in different ways. Carbon has several known allotropes, including diamonds, graphite, and Buckminsterfullerene (often known as "buckyballs"), all of which consist solely of carbon atoms arranged in distinct configurations resulting in varying properties. Diamonds exhibit a tetrahedral structure, making them extremely hard, while graphite consists of layers of carbon atoms that allow it to act as a lubricant and conductor of electricity. Buckminsterfullerene presents a spherical shape formed by carbon atoms arrayed in a pattern resembling a soccer ball. In contrast, Flourine is a halogen and a completely different element from carbon, possessing its own unique physical and chemical properties.