Final answer:
Chemists categorize coffee as a liquid and a mixture, hydrogen typically as a gas, and an egg as a solid and a complex mixture. Matter can exhibit properties of different states, such as clouds representing mixtures of gases and liquids or solids.
Step-by-step explanation:
When chemists categorize examples of matter, they look at their characteristics to determine their state: solid, liquid, gas, or plasma. Let's examine coffee, hydrogen, and an egg as different forms of matter.
Coffee can be categorized as a liquid; it takes the shape of its container and has a fixed volume as long as it's not undergoing a phase change. However, coffee is also a mixture because it contains dissolved solids in water, and the coffee beans themselves were once a solid before brewing.
Hydrogen, when referenced typically as a gas at room temperature, expands to fill any container it is in and doesn't have a fixed shape or volume. However, under extreme cold conditions or high pressure, hydrogen can become a liquid or even a solid.
Lastly, an egg is mostly categorized as a solid due its shell and the semi-solid nature of the white and yoke. The egg also is a complex mixture of proteins, fats, and water, and when cooked, exhibits both solid and liquid properties depending on how it's cooked—soft-boiled, hard-boiled, scrambled, etc.
States of Matter
Matter can often appear to have properties of more than one state. For instance, clouds behave somewhat like gases, but they are mixtures of air and tiny particles of water, which can either be in liquid or solid state. Similarly, sand can pour like a liquid but is composed of small grains of solid matter. This complexity is what makes the study of matter so interesting and important in chemistry.