1.1
matter anything that has mass and takes
up space
The nature of chemistry
The study of chemistry explores matter and its interactions. Matter is defined as
anything that has mass and occupies space. Matter might include the food you eat,
the cosmetics and grooming products you use, the battery in your cellphone, or the
gasoline in your car engine. We encounter thousands of different chemicals every day.
The potential applications of chemistry are therefore enormous.
what Is Chemistry?
It might be an interesting challenge to turn this question around and ask, “What isn’t
chemistry?” Indeed, we are hard pressed to think of many things that do not relate to
chemistry and its applications.
Chemistry is often called the central science. Chemistry helps to connect the
physical sciences (physics) and the life sciences (biology). Concepts in chemistry are
often based on an understanding of the laws of physics. For example, the concept of
ionic bonding is based on the understanding that opposite electrical charges attract
one another. These chemical concepts can, in turn, be extended to help explore concepts in biology and environmental science. For example, once we understand what
ions are and how they behave, we can apply this knowledge to the human body. This
helps us understand and predict how many body systems work.
The study of chemistry is subdivided into various branches. Inorganic chemistry,
organic chemistry, nuclear chemistry, biochemistry, and physical chemistry are some
of the different areas of chemistry.
Chemists ask questions about the nature of matter and how it interacts. They
design and conduct experiments, collecting evidence in an attempt to answer these
questions. They analyze and evaluate data. Scientists eventually develop explanations
that help them to understand what is taking place. These explanations may involve
changes on a very small scale. Often scientists use models to help them visualize
something that cannot be seen. Chemists may then make conclusions and develop
theories, which they go on to test further. Chemists need to alternate between action
in the macroscopic world (the “big” world) and thinking about the microscopic
world (the “small” world) (Figure 1).
lEARning TIP
Conceptualizing in Chemistry
Understanding concepts in chemistry
often requires trying to visualize
things that we cannot see. There are
many ways you can help yourself to
be better at this. Try using hands-on
manipulative models, working with
computer simulations, or drawing
images on paper.
experimenting
theorizing
Macroscopic world
(large things)
observing
imagining
Microscopic world
(small things)
measuring
conceptualizing
Figure 1 Chemistry involves moving back and forth between the macroscopic and the
microscopic worlds.
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Chapter 1 • Atomic Structure and the Periodic Table
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The application of this knowledge leads to advances in technology. Science involves
explaining observations about substances. Technology, however, often involves applying
these explanations to produce something useful.
The relationship between science and technology is complex. Sometimes science
leads to technological advances, but at other times technology leads to scientific discovery. As an example, scientists discovered the substance Teflon by accident. Since
then, Teflon has been used in many applications, such as a coating on cookware. You
will learn more about Teflon later in this unit.
Scientific discoveries and technological advances carry both risks and benefits. All
scientists, engineers, and technicians must be aware of the risks and benefits related
to their research. Long-term risks are often hard to foresee. For example, chlorofluorocarbons (CFCs) were once extensively manufactured and widely used. They were
effective refrigerants, cleaning solvents, and propellants in aerosol cans. Consumers
considered CFCs to be extremely beneficial substances. Then scientists discovered
that CFCs deplete the stratospheric ozone layer. Safer alternative compounds have
now replaced CFCs in most applications (Figure 2).
Figure 2 Technology has partly solved
the CFC problem by finding much safer
propellants for spray cans.
Chemistry at work
Let’s examine a specific example of chemistry at work. You are probably familiar with
three forms of carbon: charcoal, graphite, and diamond. In the late twentieth century,
scientists discovered traces of a new form of carbon, C60. They found that pure C60 is
an extremely stable substance that is able to withstand extremely high temperatures
and that has low solubility in water. These experiments provided the chemists with
empirical knowledge: knowledge that depends on observations. The chemists then
pondered how they could explain these properties. This led them to propose models
of the three-dimensional geometry of C60.
The competition to isolate and identify C60 was intense as existing theories and
new experiments worked hand in hand. Eventually, Harold Kroto, Robert Curl, and
Richard Smalley were awarded the Nobel Prize in Chemistry in 1996 for their roles
in its discovery. They proposed that its molecular shape resembles a soccer ball,
with the carbon atoms forming the pentagons and hexagons on the surface of the
sphere (Figure 3). Images of soccer balls and architectural domes helped chemists to
imagine what these molecules might look like on a molecular scale. Knowledge based
on ideas created to explain observations is known as theoretical knowledge.
The discoverers named C60 “buckminsterfullerene,” after architect Richard
Buckminster Fuller, who was famous for his work on geodesic domes. This rather
long name is often shortened to “buckyball.” The family of carbon molecules with
similar structures is known as “fullerenes.” A fullerene is any type of sphere, ellipsoid,
or tube made entirely of carbon.
(a)
(b)
(c)
empirical knowledge knowledge that
comes from investigation and observation
theoretical knowledge knowledge that
explains scientific observations
WEB LInK
In 2010 a Canadian astronomer
discovered buckyballs in space, using
NASA’s infrared telescope. To find out
more about Jan Cami’s discovery,
go T o n ElS on S C i En C E
(d)
Figure 3 (a) Pure C60 is a greyish powder. (b) Professor Harold Kroto proposed these models of buckyballs. (c) Vancouver Science World boasts a
geodesic dome designed by Buckminster Fuller. (d) Chemists now have experimental evidence for the structure of C60.
The suggested structure of a buckyball is a theory. A theory is an explanation of
evidence obtained by observation, experimentation, and reasoning. It represents
our best understanding about why something happens. It allows us to predict future
events and apply knowledge to new situations.
NEL
theory an explanation or model based
on observation, experimentation, and
reasoning
1.1 The nature of Chemistry
9
UniT TASK BooKMARK
Think of unlikely or serendipitous
developments as you plan your green
product for the Unit Task described on
page 134.
As more experimental work is done and as technology improves, theories evolve
or are discarded. Before the mid-nineteenth century, people thought that heat was a
substance. This substance, called “caloric,” appeared to flow from hot objects to cooler
ones. Experiments eventually disproved this theory and it was discarded.
As theories evolve, the body of scientific knowledge grows. For example, researchers
are looking for possible uses of the C60 molecule in materials science, electronics, and
health sciences. Buckyballs may be effective medicine delivery “cages.”
Of course, chemistry does not always happen in a series of logical steps. Creativity,
luck, and serendipity (chance) are often important.
Everyday Chemistry
Whether you are aware of it or not, you practice chemistry in your everyday life. You might
be colouring your hair, cooking, gardening, exercising, or creating art. You are continually
experimenting to achieve various objectives. Are you looking for that perfect shade of
purple for your hair? Perhaps you are trying to figure out the ideal mix of fertilizers to yield
the best crop of tomatoes. Maybe you are experimenting to find the best foods to eat before
a cross-country running meet. You observe and measure things as you proceed. You make
connections between what you changed and what happened. Often, you theorize about
why things happen the way they do. You are already a budding chemist!
IUPAC and the Scientific Community
WEB LInK
To find out more about the
importance of the International Union
of Pure and Applied Chemistry to the
chemistry community,
g o T o n El So n SCi E nCE
Chemistry is a human endeavour performed by scientists all around the world. These
scientists are driven by human emotions and actions: ambition, curiosity, wonder,
competition, hope, and perseverance. There is the need for cooperation, trust, and
governance in the scientific community. The International Union of Pure and Applied
Chemistry (IUPAC) was established in 1919 in order to help regulate standards and
procedures in chemistry. Specifically, IUPAC’s mission involves promoting the international aspects of chemistry and applying chemistry to the service of humanity. In
so doing, IUPAC promotes the values, standards, and ethics of science.
1.1 Summary
• Chemistry is the study of matter and its interactions. It is also a process for
acquiring knowledge. It is a human endeavour.
• Chemistry involves both experimenting in the macroscopic world and
theorizing about the microscopic world.
• The interplay between empirical (experimentally determined) knowledge and
theoretical knowledge is critical in the study of chemistry.
• The International Union of Pure and Applied Chemistry (IUPAC) sets rules
and standards for chemists worldwide.
1.1 Questions
10
1. What isn’t chemistry? List as many things as you can think
of that do not involve matter and its interactions. A
4. Explain the difference between empirical and theoretical
knowledge, with examples. K/U
2. (a) Distinguish between science and technology.
(b) Give a specific example of a scientific achievement and
the technology that developed as a result of it. K/U A
5. There is a lot of interest in hydrogen-powered automobiles
these days. Give an example of the science involved and an
example of a technology involved. A
3. Sometimes it is hard to foresee the long-term effects of a
chemical on the environment. K/U
(a) Give an example of a chemical that has a negative
environmental effect, and briefly describe that effect.
(b) What is being done to reduce the negative effect?
6. (a) What does the acronym IUPAC stand for?
(b) Why was this organization set up?
(c) Do you think such an organization is necessary? Defend
your position. K/U A
Chapter 1 • Atomic Structure and the Periodic Table
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