Problem 10 - An Introduction to Physical Science

Question

Choose the word or phrase that best answers the question. Which of these is a crystalline solid? A) glass C) rubber B) Sugar D) plastic

Step-by-Step Solution

Answer

B) Sugar

Step 1: Identify the properties of given materials

First, understand the definitions and properties of the given materials—glass, rubber, sugar, and plastic. Crystalline solids have a well-ordered, repeating atomic structure, whereas amorphous solids lack this regular pattern.

Step 2: Analyze each option

Evaluate each material to see if it has a crystalline structure.- Glass: Amorphous solid with no long-range order.- Rubber: Amorphous solid, typically flexible and has no crystal structure.- Sugar: Typically forms crystals and has a well-defined, repeating structure.- Plastic: Generally an amorphous solid, some may be semi-crystalline but not predominantly.

Step 3: Choose the correct answer

Based on the analysis, determine that sugar is the crystalline solid among the given options, as it forms crystals and has a clear, repeating atomic structure.

Key Concepts

Atomic Structure

Atomic structure refers to the arrangement of atoms in a substance. Understanding the atomic structure is crucial to differentiating between crystalline and amorphous solids. In crystalline solids, atoms are arranged in a well-organized, repeating pattern. This regular arrangement is called a crystal lattice. On the other hand, amorphous solids have atoms that are arranged randomly, without any long-range order.

Material Properties

Material properties stem from their atomic structures. Crystalline solids, like sugar, exhibit unique properties such as sharp melting points, high stability, and resistance to deformation. These characteristics arise from the orderly patterns of their atoms.
In contrast, amorphous solids, such as glass and rubber, lack a well-defined structure. As a result, they tend to soften over a range of temperatures and are usually more flexible. Understanding these differences helps in identifying and choosing the right materials for specific applications.

Amorphous Solids

Amorphous solids are materials where atoms are not arranged in a regular, repeating pattern. Examples include glass, rubber, and many plastics. These materials have unique properties:

• They do not have a distinct melting point.
• They are often more flexible and may gradually soften rather than melting abruptly.
• Their irregular atomic arrangement makes them less stable compared to crystalline solids.

Understanding the nature of amorphous solids is vital for various industries, such as manufacturing and materials science, where material flexibility and resilience might be crucial.