Matter and Its Properties
(Mass, Volume, and Density)
Milton Huling Ph.D.
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Printed: November 19, 2015
AUTHOR
Milton Huling Ph.D.
www.ck12.org
C HAPTER
Chapter 1. Matter and Its Properties (Mass, Volume, and Density)
1
Matter and Its Properties
(Mass, Volume, and Density)
What’s the Matter?
Here is a riddle for you to ponder: What do you and a tiny speck of dust in outer space have in common? Think you
know the answer?
Both you and the speck of dust consist of matter. So does the ground beneath your feet. In fact, everything you can
see and touch is made of matter. The only things that are not matter are forms of energy. This would include things
such as light and sound. Although forms of energy are not matter, the air and other substances they travel through
are. So what is matter? Matter is defined as anything that has mass and volume. You may recall that atoms are the
building blocks of matter. Even things as small as atoms have mass and volume. In would then seem logical that all
things made of atoms have mass and volume. The more atoms, or matter, the more mass and volume an item might
have. Different types of atoms have different amounts of mass and volume. So, it’s not enough to know the count of
atoms to determine the mass. You must also know the type of atoms an items is made of. Physical properties are all
determined by the amounts and types of atoms that compose items.
Mass
Mass is the amount of matter in a substance or object. Mass is usually measured with a balance. A simple mechanical
balance is shown in Figure below. It allows an object to be matched with other objects of known mass. The SI unit
for mass is the kilogram. For smaller masses, grams are often used instead.
You probably have a balance in your classroom. The balance may be either a triple-beam balance or an electronic
balance. The figure below of the old-fashioned balance may give you a better idea of what mass is. What would
it mean if both sides of the balance are at the same level? That’s correct, it would mean the masses of each object
would be the same. In that case, the fruit would have a mass of 1 kg. It would have the same mass as the iron. As
you can see, the fruit is at a higher level than the iron. This means the fruit has less mass than the 1 kg iron object.
Q: What If the fruit were at a lower level than the iron object?
A: The mass of the fruit would be greater than 1 kg.
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Mass versus Weight
Mass is commonly confused with weight. The two are closely related, but they measure different things. Mass is the
amount of matter in an object. Weight is a measure of the force of gravity acting on an object. On Earth, the force
of gravity is constant. If we are comparing objects on Earth, objects with a greater mass also have a greater weight.
Weight is measured with a device called a scale. Remember, mass is measured with a balance. An example of a
scale might be a kitchen or bathroom. Scales detect how forcefully objects are being pulled downward by gravity.
The SI unit for weight is the newton (N). A mass of 10 kg has a weight of 100 newtons (N).
Problem Solving
Problem: At Earth’s gravity, what is the weight in newtons of an object with a mass of 10 kg?
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Chapter 1. Matter and Its Properties (Mass, Volume, and Density)
Solution: At Earth’s gravity, 1 kg has a weight of 9.8 N. Therefore, 10 kg has a weight of (10 x 9.8 N) = 98 N.
You Try It!
Problem: If you have a mass of 50 kg on Earth, what is your weight in newtons?
An object with more mass is pulled by gravity with greater force. Mass and weight are closely related. However, the
weight of an object can change if the force of gravity changes. In contrast, the mass of the object remains constant.
Look at the photo of astronaut Edwin E. Aldrin Jr taken by fellow astronaut Neil Armstrong in the Figure below.
They were the first humans to walk on the moon. An astronaut weigh s less on the moon than he would on Earth.
This is because the moon’s gravity is weaker than Earth’s. The astronaut’s mass, on the other hand, did not change.
He still contained the same amount of matter on the moon as he did on Earth.
If the astronaut weighed 175 pounds on Earth, he would have weighed only 29 pounds on the moon. If his mass on
Earth was 80 kg, what would his mass have been on the moon? [Figure 3]
Volume
The amount of space matter takes up is its volume. How the volume of matter is measured depends on its state.
The volume of liquids is measured with measuring containers. In the kitchen, liquid volume is usually measured
with measuring cups or spoons. In the lab, liquid volume is measured with containers such as graduated cylinders.
Units in the metric system for liquid volume include liters (L) and milliliters (mL).
The volume of gases depends on the volume of their container. That’s because gases expand to fill whatever space
is available to them. For example, as you drink water from a bottle, air rushes in to take the place of the water. An
"empty" liter bottle actually holds a liter of air. How could you find the volume of air in an "empty" room?
The volume of regularly shaped solids can be calculated from their dimensions. For example, the volume of a
rectangular solid is the product of its length, width, and height (l x w x h). For solids that have irregular shapes,
the displacement method is used. You can see how it works in the Figure below and in the video below. The SI
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unit for solid volumes is cubic meters (m3). However, cubic centimeters (cm3) are often used for smaller volume
measurements.
The displacement method is used to find the volume of irregularly shaped objects. It measures the amount of water
that the object displaces, or moves out of the way. What is the volume of the toy dinosaur in mL? [See Figure below]
For a video on the displacement method, go to this URL: http://www.youtube.com/watch?v=e0geXKxeTn4 .
MEDIA
Click image to the left or use the URL below.
URL: http://www.ck12.org/flx/render/embeddedobject/79976
Q: How could you find the volume of air in an otherwise empty room?
A: If the room has a regular shape, you could calculate its volume from its dimensions. For example, the volume of
a rectangular room can be calculated with the formula:
Volume = length × width × height
If the length of the room is 5.0 meters, the width is 3.0 meters, and the height is 2.5 meters, then the volume of the
room is:
Volume = 5.0 m × 3.0 m × 2.5 m = 37.5 m3
Q: What is the volume of the dinosaur in the diagram above?
A: The volume of the water alone is 4.8 mL. The volume of the water and dinosaur together is 5.6 mL. Therefore,
the volume of the dinosaur alone is 5.6 mL – 4.8 mL = 0.8 mL.
Lesson Summary
• Matter is anything that has mass and volume. Mass is the amount of matter in a substance. Volume is the
amount of space matter takes up.
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Chapter 1. Matter and Its Properties (Mass, Volume, and Density)
• Matter has both physical and chemical properties. Physical properties can be measured or observed without
matter changing to a different substance.
• Chemical properties of matter can be measured or observed only when matter undergoes a change to become
an entirely different substance.
Advanced Topic: Defining Density
Density is also an important physical property of matter. The concept of density combines what we know about an
objects mass and volume. Density reflects how closely packed the particles of matter are. When particles are packed
together more tightly, matter is more dense. Differences in density of matter explain many phenomena. It explains
why helium balloons rise. It explains why currents such as the Gulf Stream flow through the oceans. It explains
why some things float in or sink. You can see this phenomenon by pouring vegetable oil into water. You can see a
colorful demonstration of substances with different densities at this URL:
http://www.youtube.com/watch?v=B3kodeQnQvU (4:00)
MEDIA
Click image to the left or use the URL below.
URL: http://www.ck12.org/flx/render/embeddedobject/54886
To better understand density, think about a bowling ball and volleyball, pictured in the Figure 1.1. Imagine lifting
each ball. The two balls have about the same volume. The bowling ball feels much heavier than the volleyball, but
why? It is because the bowling ball is made of solid plastic. Plastic contains a lot of tightly packed particles of
matter. In contrast, the volleyball is full of a gas (air). The air atoms are further apart than in the solid bowling ball.
Therefore, the matter inside the bowling ball is denser than the matter inside the volleyball.
FIGURE 1.1
A bowling ball is denser than a volleyball.
Although both balls are similar in size, the
bowling ball feels much heavier than the
volleyball.
Q: If you ever went bowling, you may have noticed that all the bowling balls are the same size. This means they
have the same volume. Even though they are the same size, some bowling balls feel heavier than others. How can
this be?
A: Bowling balls that feel lighter are made of matter that is less dense.
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Calculating Density
The density of matter is actually the amount of matter in a given space. The amount of matter is measured by its
mass. The space matter takes up is measured by its volume. Therefore, the density of matter can be calculated with
this formula:
Density =
mass
volume
Assume, for example, that a book has a mass of 500 g and a volume of 1000 cm3 . Then the density of the book is:
Density =
500 g
= 0.5 g/cm3
1000 cm3
Q: What is the density of a liquid that has a volume of 30 mL and a mass of 300 g?
A: The density of the liquid is:
Density =
300 g
= 10 g/mL
30 mL
Explore More
Go to this URL and take the calculating-density quiz. Be sure to check your answers!
http://www.old-pz.gse.harvard.edu/ucp/curriculum/density/s2_resources_calculating_density.pdf
Summary
• Matter is all the “stuff” that exists in the universe. It has both mass and volume.
• Mass measures the amount of matter in a substance or an object. The basic SI unit for mass is the kilogram
(kg).
• Volume measures the amount of space that a substance or an object takes up. The basic SI unit for volume is
the cubic meter (m3 ).
• Density is an important physical property of matter. It reflects how closely packed the particles of matter are.
Explore More
Do the mass and volume quiz at this URL. Be sure to check your answers.
http://www.proprofs.com/quiz-school/story.php?title=measurement-mass-volume
Review
1. How do scientists define matter?
2. What is mass? What is the basic SI unit of mass?
3. What does volume measure? Name two different units that might be used to measure volume.
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4.
5.
6.
7.
Chapter 1. Matter and Its Properties (Mass, Volume, and Density)
Explain how to use the displacement method to find the volume of an irregularly shaped object.
What is density?
Find the density of an object that has a mass of 5 kg and a volume of 50 cm3 .
Create a sketch that shows the particles of matter in two substances that differ in density. Label the sketch to
show which substance has greater density.
Define matter.
How does mass differ from weight?
Describe the displacement method for measuring the volume of an object.
Apply Concepts
Create a table comparing and contrasting physical properties of tap water and table salt.
Apply the concept of density to explain why oil floats on water.
Think Critically
Some kinds of matter are attracted to a magnet. Is this a physical or chemical property of matter? How do you
know?
Points to Consider
The physical and chemical properties of substances can be used to identify them. That’s because different kinds of
matter have different properties.
What property could you use to tell the difference between iron and aluminum?
How could you tell whether a liquid is honey or vinegar?
References
1. User:Batholith/Ja.Wikipedia. http://commons.wikimedia.org/wiki/File:Kitchen_scale_20101110.jpg .
2. Courtesy of Neil Armstrong and NASA. http://images.ksc.nasa.gov/photos/1969/captions/AS11-40-5875.htm
l .
3. Bowling ball: Matthew (Flickr: falcon1961); Volleyball: User:Amada44/Wikimedia Commons. A bowling
ball is denser than a volleyball . Bowling ball: CC BY 2.0; Volleyball: Public Domain
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