Page 34 - Utah Science Textbook
P. 34
Find the Mass of a Gas
You might be able to imagine, however, the difficulty for people several hundred years
ago to demonstrate that air has mass and volume. Air (and all other gases) are invisible to
the eye, have very small masses compared to equal amounts of solids and liquids, and are
quite easy to compress (change volume). Without sensitive equipment, it would have
been difficult to convince people that gases are matter. The mass of air, under normal
room conditions, that occupies a one quart jar is approximately 0.0002 pounds. This small
amount of mass would have been difficult to measure in times before balances were
designed to accurately measure very small masses. Later, scientists were able to compress
gases into such a small volume that the gases turned into liquids, which made it clear that
gases are matter.
Review Questions for Standard 1
Objective 2
1. In your own words explain what matter is and give three examples of things that are
made of matter.
2. Explain what mass is and tell how scientists determine the mass of an object.
3. What metric units are used to report the mass of an object?
4. Distinguish the difference in mass and weight.
5. How is weight affected by gravity?
6. Explain how to use a triple beam balance to determine the mass of an object.
7. Explain how to determine the volume of a regularly shaped solid such as a cube.
8. Explain how to determine the volume of an irregularly shaped object such as a rock.
9. What are physical properties of matter?
10. What two measurements are needed to determine density?
11. Explain how to determine density.
12. What happens when a solid object with a lower density is placed in a liquid with a
greater density?
13. What happens when an object with a lower density is placed in a container with an
object with a higher density?
14. Explain how you could determine the mass and volume of a gas.
35
You might be able to imagine, however, the difficulty for people several hundred years
ago to demonstrate that air has mass and volume. Air (and all other gases) are invisible to
the eye, have very small masses compared to equal amounts of solids and liquids, and are
quite easy to compress (change volume). Without sensitive equipment, it would have
been difficult to convince people that gases are matter. The mass of air, under normal
room conditions, that occupies a one quart jar is approximately 0.0002 pounds. This small
amount of mass would have been difficult to measure in times before balances were
designed to accurately measure very small masses. Later, scientists were able to compress
gases into such a small volume that the gases turned into liquids, which made it clear that
gases are matter.
Review Questions for Standard 1
Objective 2
1. In your own words explain what matter is and give three examples of things that are
made of matter.
2. Explain what mass is and tell how scientists determine the mass of an object.
3. What metric units are used to report the mass of an object?
4. Distinguish the difference in mass and weight.
5. How is weight affected by gravity?
6. Explain how to use a triple beam balance to determine the mass of an object.
7. Explain how to determine the volume of a regularly shaped solid such as a cube.
8. Explain how to determine the volume of an irregularly shaped object such as a rock.
9. What are physical properties of matter?
10. What two measurements are needed to determine density?
11. Explain how to determine density.
12. What happens when a solid object with a lower density is placed in a liquid with a
greater density?
13. What happens when an object with a lower density is placed in a container with an
object with a higher density?
14. Explain how you could determine the mass and volume of a gas.
35
