Chapter 1 Notes

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Chapter 1
Chemistry: The Science of Matter
Fill in the blanks in your notes with the words bolded in
orange.
Warm Up Question
List the senses that can be used
to make an observation.
Which one should definitely not
use in a chemistry lab?
9/10
The Scientific Method

The scientific method is the systematic
approach used in scientific study.



Observation: is the act of gathering information by
using your senses on a macroscopic level.
Hypothesis: is a testable prediction used to
explain an observation (if, then).
Experiment: is a set of observations used to test a
hypothesis.


Control, independent variable, dependent variable
Conclusion: addresses whether or not the
hypothesis is supported by the results
The Scientific Method
Theory vs. Law


Theory: is an explanation based on many
observations and supported by the results of many
experiments.
Scientific law: is a fact of nature that is observed
so often that it is accepted as the truth.
Explanation
Arise following
many, many
experiments
Statement
Benchmark
If you haven’t done so already, you can now
Complete homework #1, part A.
Review slides 3-5 and your notes to help you
answer these questions. You will not find the
answers in your book.
Exit Question
Read the following experiment:
Gloria wanted to find out if the color of food
would affect whether kindergarten children
would select it for lunch. She put food coloring
into 5 identical bowls of mashed potatoes. The
colors were plain, red, green, yellow, and blue.
Each child chose a scoop of potatoes of the
color of their choice.
What do you think the results would be?
Write a hypothesis for this experiment using a
“If…..then statement.
Warm up Question
9/12
Write 3 words to describe this substance
Matter & its Properties

Chemistry is the science that investigates and
explains the structure and properties of matter.


Matter is anything that takes up space and has
mass.
Mass is the measure of the amount of matter that
an object contains.
Mass is not the same as weight. Weight is affected
by gravity where mass is not.

The properties of matter describe the
characteristics and behavior of matter,
including the changes that matter undergoes.
Matter & its Properties
Physical Properties

Characteristics that a
sample of matter
exhibits without any
change in its identity.
Chemical Properties

The ability of a
substance to combine
with or change into
one or more other
substances.
Matter & its Properties
Matter & its Properties
Macroscopic

Matter that is large
enough to be seen.
Microscopic

Matter that cannot be
seen with the naked
Matter & its Properties
Qualitative

An observation that
can be made without
measurement.
Quantitative

An observation that
uses measurement.
Benchmark
If you haven’t done so already, you should read
pages 3-15 in your textbook.
With the reading, slides 9-13, and your notes
should be able to complete homework #1, part B.
Exit Question
Is color a physical or chemical property
of matter? Explain
9/20
Warm up Question
Both of these are mixtures.
Explain how they are different from one
another (besides their physical states)
Classifications of Matter
Mixtures
A mixture is a combination of two or more
substances in which the basic identity of each
substance is not changed.
►
Mixtures can be separated into its components by physical
processes.
Heterogeneous Mixture

A mixture with
different compositions.
Homogeneous Mixture

A mixture that is the
same throughout.

It is also referred to as
a solution.
Types of Solutions
Solid Solutions:

Alloys are solid solutions that contain different metals
and sometimes nonmetallic substances.
Liquid Solutions:


The solute is the substance that is being dissolved.
The solvent is the substance that does the dissolving.

When the solvent is water, the solution is called an aqueous
solution.
Separation Techniques

Filtration


Distillation


Used to separate a liquid mixture.
Crystallization


Used to separate a mixture with widely varying particles
size.
Used to separate an aqueous solution.
Chromatography

Separates a mixture based on polarity.
Benchmark
If you haven’t done so already, read pages 18-31.
With the reading, slides #17-20, and your notes,
you should be able to complete homework #2,
part A.
Exit Question
What kind of mixture does this represent?
How could you separate it into its individual components?
Warm up Question
9/14
Name the separation technique is used
to make coffee or tea?
Physical Change
A physical change is a change in matter that
does not involve a change in the identity of
individual substances.




Matter exists in one of three states (solid, liquid, or
gas) depending on its temperature.
Any change in state is a physical change.
If a substance is described as being volatile, it
becomes a gas easily at room temperature.
Mixtures are separated by a physical change
Substances
Compounds


This type of pure
substance can be
broken down into
simpler substances.
It is a chemical
combination of two or
more different
elements joined
together in a fixed
proportion.
Elements


This type of pure
substance cannot be
broken down into
simpler substances.
They are the simplest
form of matter.
Compounds
The properties of a compound are different from
the properties of the elements that compose the
compound.

A formula is a combination of the chemical symbols
that show what elements make up a compound and
the number of atoms of each element.
A substance is matter with the same fixed
composition and properties.


Things that are pure are made up of only one kind
of matter.
Compounds are separated into their component
elements by chemical means.
Chemical Change

A chemical change is a process that involves
one or more substances changing into new
substances.


It is also referred to as a chemical reaction.
The law of conservation of mass (matter) says
that in a chemical change matter is neither created
nor destroyed.
C25H52 + 38 O2 --> 25 CO2 + 26 H2O
Energy Change

Chemical changes involve an energy change.

Energy is the capacity to do work.



Work is done whenever something is moved.
Chemical reactions that give off heat energy are called
exothermic reactions.
Chemical reactions that absorb heat energy are called
endothermic reactions.
Benchmark
If you haven’t done so already, read pages 18-31.
With the reading, slides #24-28, and your notes,
you should be able to complete homework #2,
Part B.
Exit Question
List which of the following represent a
physical change?
Warm-up Question
9/24
Assuming that both of these objects take
up the same space, state which object is
more dense. Explain
Wood
Steel
Density

Density is a physical property of matter.


Density is the amount of matter (mass) contained
in a unit of volume.
The density of solids and liquids is usually
measured in grams (mass) per milliliter (volume).



g/ml
For irregularly shaped objects, water displacement
is used to obtain a volume measurement.
Formula:
Density

Examples…

What is the density of a piece of wood that has a
mass of 25.0 grams and a volume of 29.4 cm3?

I threw a plastic ball in the pool for my dog to fetch.
The mass of the ball was 125 grams. What must
the volume be to have a density of 0.500 g/ml? I
want the ball to float, of course!
Benchmark
If you haven’t done so already, read pages 34-44.
With the reading, slides #32-34, and your notes,
you should be able to complete homework #5.
Be proud of yourself, you just made it
through your first unit in chemistry!
Exit Question
List which of the following represent a
chemical change?
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