Problem 98 - Chemistry: The Central Science

Question

What evidence supports the notion that buckyballs are actual molecules and not extended materials? (a) Buckyballs are made of carbon. (b) Buckyballs have a well-defined atomic structure and molecular weight. (c) Buckyballs have a well-defined melting point. (d) Buckyballs are semiconductors. (e) More than one of the previous choices.

Step-by-Step Solution

Answer

The correct answer is (e) More than one of the previous choices, as both (b) Buckyballs have a well-defined atomic structure and molecular weight, and (c) Buckyballs have a well-defined melting point, provide evidence that buckyballs are actual molecules.

Step 1: Understanding the difference between molecules and extended materials

First, let's understand the difference between a molecule and an extended material. A molecule is formed when two or more atoms join together chemically and has a definite structure and composition, whereas an extended material is a continuous arrangement of atoms, ions, or molecules over a large scale without a definite structure or composition.

Step 2: Analyzing option (a)

(a) Buckyballs are made of carbon. This statement is true. Buckyballs, also known as fullerene, are a type of carbon allotrope, made entirely of carbon atoms. However, this fact alone does not provide definitive evidence that buckyballs are molecules instead of extended materials, since other carbon-based materials, like graphene or diamond, also consist of carbon atoms and can be extended materials.

Step 3: Analyzing option (b)

(b) Buckyballs have a well-defined atomic structure and molecular weight. This statement also holds true for buckyballs, which are composed of 60 carbon atoms arranged in a soccer-ball like structure, and have a definite molecular weight. The well-defined structure and molecular weight are important characteristics of a molecule, as opposed to extended materials. Thus, this option provides strong evidence that buckyballs are actual molecules.

Step 4: Analyzing option (c)

(c) Buckyballs have a well-defined melting point. A well-defined melting point is characteristic of a substance with a stable molecular structure, since it indicates the temperature at which the bonds between the molecules break down. This fact further supports the idea that buckyballs are actual molecules, rather than extended materials.

Step 5: Analyzing option (d)

(d) Buckyballs are semiconductors. While it is true that buckyballs possess properties of semiconductors, this fact is not sufficient to classify them as molecules or extended materials. Semiconducting properties can be found in both molecular and extended materials, so this option does not provide definitive evidence that buckyballs are actual molecules.

Step 6: Deciding on the correct answer(s)

Based on our analysis, options (b) and (c) provide evidence that buckyballs have characteristics of actual molecules, rather than extended materials. Option (a) is true, but it doesn't provide conclusive evidence. Option (d) is also correct, but it doesn't differentiate between molecules and extended materials. Therefore, the correct answer is (e) More than one of the previous choices, as both (b) and (c) provide evidence that buckyballs are actual molecules.