Question

Define matter. Which are examples of matter? (a) air, (b) an idea, (c) a bowl of soup, (d) a squirrel, (e) sodium chloride, \((\mathbf{f})\) the sound of an explosion

Short answer

Matter is anything with mass and occupies space. Examples of matter include air, a bowl of soup, a squirrel, and sodium chloride. An idea and the sound of an explosion are not matter.

Step-by-step solution

- Defining Matter

Identify the characteristics of matter. Matter is anything that has mass and occupies space. Matter is made of atoms and molecules and it can be in the form of a solid, liquid, gas, or plasma.

- Evaluating Examples

Examine each example to determine if it fits the definition of matter. We must decide if each example has mass and occupies space.

- Identifying Matter

(a) Air is a mixture of gases that has mass and occupies space, therefore it is matter. (b) An idea is a concept, it does not have mass nor does it occupy space, so it is not matter. (c) A bowl of soup is composed of various substances that have mass and take up space, it is matter. (d) A squirrel is a living organism with mass and volume, making it matter. (e) Sodium chloride is a chemical compound that consists of ions with mass and takes up space, so it is matter. (f) The sound of an explosion is a wave that travels through matter but does not itself have mass or occupy space independently; it is not considered matter.

Key concepts

Characteristics of Matter

Understanding the characteristics of matter is crucial for identifying the material world around us. Matter, at its core, is anything that possesses mass and volume, meaning it has weight and occupies space. But don't get tricked into thinking it's just things you can touch—sometimes matter can be invisible, like air!

Let's get into the details. Matter is made up of tiny particles called atoms and molecules, which are in constant motion. The way these particles are arranged and how they move determines the form matter takes—be it a solid, liquid, gas, or even plasma. Matter can change from one state to another, for instance, water can evaporate into steam or freeze into ice.

Is Everything Matter?

Not everything we experience is matter. For instance, concepts and emotions—like love, fear, or an idea you come up with—don't qualify as matter because they don't have mass or take up space. Let's keep this in mind as we examine the examples in the textbook exercise.

States of Matter

Speaking about the states of matter gets pretty interesting. Like characters in a play, particles within matter can act out solids, liquids, gases, and plasma under different conditions.

Solids have a defined shape and volume because their particles are packed closely together and only vibrate slightly. Picture a cube of sugar—it holds its shape unless you crush it. Liquids have a definite volume but no fixed shape; they flow and fill the container they're in, like water in a glass. Gases, such as the air we breathe, have neither a fixed shape nor volume; they expand to fill the available space completely. Plasma is more exotic—it's a superheated gas with charged particles, seen in places like the sun and fluorescent light bulbs.

Easy to Visualize

Imagine you're holding a balloon. It's solid rubber (though stretchy), filled with gas (air), and if it has some water inside, that's your liquid. Three states of matter in one simple object!

Mass and Volume

To become a master of matter, wrapping your head around mass and volume is essential. Mass refers to the amount of matter in an object and is typically measured in grams or kilograms. It's the 'how heavy' factor when you pick something up. Volume, on the other hand, is a measure of the space that object takes up, which is usually measured in liters or cubic meters.

Understanding the distinction helps us in many real-life scenarios. For example, when packing for a trip, your suitcase has a limit in mass (weight allowance) and volume (space it can contain). Both characteristics must be considered to maximize your packing efficiency.

Consistent and Variable

Interestingly, while an object's mass remains consistent irrespective of its location, its weight—an effect of gravity—can change. However, the volume of liquids and gases can vary considerably with temperature and pressure, unlike the fixed volume of solids.

Atoms and Molecules

Atoms and molecules are the building blocks of matter, tiny particles that are way too small to see but make up everything in our physical world. An atom is the smallest unit of an element that still retains the element's chemical properties. On the other hand, a molecule is formed when two or more atoms join together through chemical bonds.

Ranging from the oxygen we breathe, which is made up of O2 molecules, to the more complex DNA molecules that carry genetic information in cells, atoms and molecules come in countless combinations creating the diverse array of substances we encounter every day.

Bonding Basics

The bonds holding atoms together in molecules are like the hands of a team in a tug-of-war—they can be strong or weak, and they determine the molecule's stability and how it interacts with other molecules. Remember, without atoms and molecules, there wouldn't be matter as we know it!