Question

Which physical state is described as having a fixed shape and fixed volume?

Short answer

Solids have a fixed shape and fixed volume.

Step-by-step solution

Identify the Three States of Matter

Matter can exist in three primary states: solid, liquid, and gas. Each of these states has distinct characteristics regarding shape and volume.

Examine the Characteristics of Solids

Solids have a fixed shape and fixed volume. This means solids hold their shape and do not adapt to the shape of their container. The particles in a solid are closely packed together, which gives them their definite shape and volume.

Compare with Liquids and Gases

Liquids have a fixed volume but take the shape of their container, meaning their shape is not fixed. Gases have neither a fixed volume nor a fixed shape, as they expand to fill their container. This comparison confirms that solids uniquely have both a fixed shape and volume.

Key concepts

Physical Properties of Solids

Solids are one of the primary states of matter with distinct characteristics that make them different from liquids and gases. They have a fixed shape and a fixed volume. This means that no matter where you place a solid, it will retain its shape and size. Solids do not flow or conform to the shape of a container, unlike liquids and gases.

The defining feature of solids is the close packing of their particles. These particles are tightly packed, often in a regular arrangement, leading to minimal movement between them. This close interaction results in a rigid structure. Because of this arrangement, solids generally have a high density compared to other states of matter.

Furthermore, solids can be characterized by their strength and resistance to forces. This is why we utilize solids for constructing things that require stability and strength, like buildings or bridges. Understanding the physical properties of solids helps us appreciate their role in various applications in everyday life.

Characteristics of Liquids

Liquids differ from solids in several key ways. While a liquid has a definite volume, it does not have a fixed shape. It takes the shape of the container it occupies. This property allows liquids to flow and change shape depending on their surroundings.

The particles in a liquid are not as tightly packed as in solids. They are close but have more space to move around each other. This molecular freedom provides liquids their fluidity, which is why you can pour them and watch them flow. Viscosity, the measure of a liquid's resistance to flow, varies between different liquids. For instance, honey flows more slowly than water due to its higher viscosity.

Another remarkable feature of liquids is surface tension, the energy required to increase the surface area of a liquid. This causes phenomena like water droplets forming beads on a surface. Understanding the characteristics of liquids is crucial for various practices, including cooking, manufacturing, and even biology.

Characteristics of Gases

Gases stand apart due to their lack of fixed shape and volume. They expand to fill the entire volume of their container, regardless of its shape or size. This means that if you release a gas in an enclosed space, it will spread out evenly until it fills the space.

The particles in a gas are much farther apart than in solids and liquids. Due to this significant distance between particles, gases are compressible, meaning their volume can be significantly reduced when pressure is applied. This is not the case with solids and liquids.

One fascinating property of gases is their tendency to diffuse, which means they can spread out and mix with other gases quickly. This is why when someone sprays perfume in one corner of a room, the scent soon travels throughout the space. Gases also play crucial roles in various fields, such as respiration, where oxygen is essential for life, and in industrial applications, where gases like nitrogen and argon are used for processes including welding and preserving food.