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Living By Chemistry
Unit 1: ALCHEMY
Matter, Atomic Structure, and Bonding
In this unit you will learn:
• what matter is composed of
• to use the language of chemistry
• to decode information contained in the
periodic table
• how new substances with new properties
are made
• what holds substances together
Section I: Defining Matter
Lesson 1 Tools of the Trade
Lesson 2 A Penny for Your Thoughts
Lesson 3 What’s the Matter?
Lesson 4 Mass Communication
Lesson 5 All That Glitters
Lesson 1: Tools of the Trade
Lab Equipment and Safety
• recognize common chemistry tools and
equipment that you will be using in the course
• find all the safety equipment in the laboratory
and understand its use
• understand the rules of safety in the chemistry
laboratory
Discussion Notes
Safety Equipment:
fire blanket
fire extinguisher
eye wash
safety goggles
First aid kit
Aprons/lab coat
Shower
hood
Safety behaviors:
Chemistry labs have a number of
potential hazards!
Know the procedures
Use all chemicals properly
No horseplay
Keep lab area neat/clean
Watch hair/clothing around flames
Lesson 2: A Penny for Your
Thoughts
Introduction to Chemistry
Key Question
What is chemistry?
Long ago, early scientists tried to turn ordinary things
into gold. This pursuit was called alchemy, and the
people who engaged in alchemy were called
alchemists.
You will be able to:
• observe a procedure and write observations
• define and formulate a hypothesis to explain
observed phenomena
• define chemistry and begin to describe what
chemists study
What is Chemistry?
The study of substances, their properties, and how they can be transformed.
The study of matter and how matter can be changed.
Let’s Do
CHEMISTRY
A Penny for your Thoughts
Purpose: observe a chemical transformation.
Do you think you changed the penny to gold?
How would you be able to tell for sure?
Discussion Notes
To determine whether the new penny is gold, you
need to study its properties.
Property: A characteristic of a substance.
Matter has observable and measurable qualities.
We can use general properties to identify substances.
All substances have properties…
Example:
People can be identified by their …
Face (shape,
expressions) Voice Height Finger prints
Eye color Hair color Teeth DNA
Physical Properties: Characteristic of a substance
that can be observed without changing the substance
into something else.
for example: mass, color, hardness, size, texture, odor
Chemical Properties: characteristics involved when
a substance interacts with another substance to
change its chemical make-up.
for example: pH, flammability, rusting (oxidizing), gassing
Properties are used to identify, describe
and classify matter.
examples of physical properties
commonly used in chemistry:
state, freezing point, boiling point, melting point, viscosity, density, luster and many more.
• viscosity - The resistance of a liquid to flowing.
Low viscosity-water, rubbing alcohol
High viscosity-honey
Physical properties of matter are categorized as
either: Intensive or Extensive:
Intensive - Properties that do not depend on the amount of the matter present.
• color, odor, luster
• malleability, ductility, conductivity
• density
Extensive – Properties that change when the size of the sample changes.
• mass, volume, length
• total charge
Chemical properties
A common chemical property is reactivity.
• Reactive to oxygen
• Reactive to air
• Reactive to water…
Note that chemical properties
aren’t EASY to observe,
unlike physical properties.
examples of chemical properties
commonly used in chemistry:
Flammability, corrosivity, oxidation state, and more
• oxidation - The loss of electrons.
When a substance is oxidized, it’s properties change
for example –
silver tarnishes
metals rust
Did you know?
Fruit exposed to the air is oxidized (the oxygen steals
electrons from the compounds in the fruit’s cells) and
turns brown.
The process is very similar to the
rusting process of metals. The
oxidized form of these compounds
is different from the unoxidized form
and is, unfortunately, unappealing
to eat.
antioxidants
Many 'superfoods' are advertised as containing
antioxidants. An antioxidant is a compound that
reduces the oxidation of other compounds.
In theory, consuming antioxidants will help our bodies
fight off the harmful effects of oxidation, keeping our
cells and enzymes happy and healthy. In other words,
eating things like blueberries and chocolate will
help our insides from looking like
browning fruit.
How do you know if it is a
chemical or physical property?
If it can Change and can’t be reversed, it’s
CHemical
Do you think you changed the penny to gold?
How would you be able to tell for sure?
More discussion Notes in text..
Scientists use a systematic approach to solve problems
in science.
Hypothesis: A testable prediction or explanation
for an observation.
If I changed the copper into gold, then the penny
will exhibit physical and chemical properties
associated with the element gold.
Lesson 2 summary:
What is chemistry?
• Chemistry is the study of what substances are
made of, how they behave, and how they can be
transformed. It is the study of matter and how
matter can be changed.
• Matter can be identified by its chemical and
physical properties.
• A hypothesis is a testable explanation for an
observation.
• Scientists use a systematic approach to solving
problems in science.
Lesson 3: What’s the Matter?
Defining Matter
• define matter
• classify an item as matter or not matter
You will be able
to:
Remember?
1.How do we define matter?
2.Name two things that are matter and two
things that are not matter.
Discussion Notes
Items that are clearly matter are all objects, or
things, that are tangible.
Energy and ideas are not matter, but they
involve matter.
Matter has some sort of dimension and
substance to it.
A good definition should work 100% of the time.
Here are some textbook definitions of matter:
Matter: Anything that has substance and takes up
space.
Matter: Anything that has mass and volume.
wind clouds music
Everything that has mass and takes up space is matter,
yet some things do not consist of matter.
Here is a list of 10 examples of non-matter. Basically, any
type of energy or any abstract concept is an example of
something that is not matter.
time sound
light color
love thoughts
gravity microwaves
heat memories
information reflections
Why aren’t light and heat matter?
The universe consists of matter and energy. The
Conservation Laws state that the total amount of matter
and energy are constant in a reaction, but matter and
energy may change forms.
Energy describes the ability to cause change. While
matter may have energy, they are different from each
other.
One easy way to tell matter and energy apart is to ask
yourself whether what you observe has mass. If it
doesn't, it's energy!
Examples of energy include any part of the
electromagnetic spectrum, which includes visible light,
infrared, ultraviolet, x-ray, microwaves, radio, and gamma
rays.
Other forms of energy are heat (which may be considered
infrared radiation), sound, potential energy, and kinetic
energy.
Another way to distinguish between matter and energy
is to ask whether something takes up space. Matter
takes up space. You can put it in a container. While
gases, liquids, and solids take up space, light and heat
do not.
Usually matter and energy are found together, so it can
be tricky to distinguish between them. For example, a
flame consists of matter in the form of ionized gases and
particulates and energy in the form of light and heat.
You can observe light and heat, but you can't weigh
them on any scale.
summary
Chemists study all kinds of matter.
• Matter is everything that has substance and
takes up space, or that has mass and
volume.
• Your brain is an example
of matter, ideas are not.
Lesson 4: Mass Communication
Mass and Volume
Would it hurt more to be hit with 5
pounds of feathers or 5 pounds of
bricks?
Key concept
How do you determine the masses and
volumes of different substances?
• measure mass using a balance
• measure the volume of regularly and irregularly
shaped objects
Skills to master:
Discussion Notes
Mass is commonly measured in units of grams (g)
or kilograms (kg).
1 kg = 1000 g
Discussion Notes (cont.) Volume is a measure of the amount of space occupied by something.
1000 mL = 1 L
1 mL = 1 cm3
Mass: A measure of the quantity of matter in an object.
Volume: The amount of space a sample of matter occupies
Prepare for the Lab
To the nearest
hundredth of a milliliter,
the volume of liquid is
5.52 mL.
In this lab, you will be
measuring volume with a
graduated cylinder or
calculating directly based on
formulas for volume of solids.
If a solid is rectangular or cylindrical, you can find its
volume by measuring its dimensions and using a
geometric formula.
Measuring volume using
displacement method
remember: volume is a
measurement of the
amount of space a
substance occupies.
summary
How do you determine the masses and volumes of
substances?
• Mass is a measure of the amount of substance.
Mass can be measured using an electronic or
triple beam balance.
• Volume is the amount of space occupied by an
object. The volume of a liquid can be measured
in a graduated cylinder.
• Objects with similar volumes can have different
masses, and vice versa.
post note: Significant digits
Exact measurement
plus one estimate.
Indicates the accuracy of the measuring
instrument.
Determining The Correct Number Of Significant
Digits
After performing a calculation, we often obtain more
digits than are warranted by the measurements that
produced it. In order to determine the correct number of
significant digits in the answer, there are two different
methods depending on which mathematical operation
was performed.
Get chemistry help.
Check-in
A penny has a mass of 2.498 g.
a. What is the mass to the nearest tenth of a gram?
b. How would you determine the volume of a penny?
c. What is the difference between mass and volume?
d. Suppose you find that the golden penny has a mass of 2.6 g. If you compare it with the mass of this penny, what can you conclude?
Lesson 5: All That Glitters
Density
Key Question
How can you use mass and volume to determine
the identity of a substance?
You will be able to: • define density as the amount of mass in a
certain space, or mass per unit volume
• solve problems for density, mass, or volume
using the equation D = m/V
• explain how and why density can be used to
identify a substance.
Discussion Notes
Density is an extensive property of matter.
Discussion Notes
Common materials and their densities.
Material Density Material Density
zinc 7.1 g/cm3 gold 19.3 g/cm3
paper 0.9 g/cm3 brass 8.4 g/cm3
water 1.0 g/mL copper 9.0 g/cm3
aluminum 2.7 g/cm3 lead 11.4 g/cm3
Additional analysis:
de
nsity
• Line of best fit
• determine
unknown
summary
How can you use mass and volume to determine the
identity of a substance?
• One substance can be distinguished from
another by examining its intensive physical
properties, such as density.
• Density is a measure of the mass per unit
volume of a substance.
• The density of any given substance is always the
same (as long as the temperature remains
constant).
How could you use density to find out the
composition of a penny?
What year did the penny composition change?
How thick is a piece of aluminum foil?
Check-in In 1999, the United States Mint produced a coin called the Golden Dollar. It features an image of Sacagawea, the famous Native American guide for Lewis and Clark. It has a mass of 9.8 g and volume of 1.1 mL.
Is this coin truly gold?
Explain. (The density of gold
is 19.3 g/mL.)
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