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Matter & Change
Chapter 1
Pages 3 - 20
Chemistry is a Physical
Science
The physical sciences focus on ________________.
Why is chemistry central to all the sciences?
Chemistry is defined as: ______ 
What two questions do chemists answer through work in the
lab?
How many branches of chemistry are listed in your text book?
List these branches.
Which of these branches do you think is most important to
human society as you know it be today?
Chemistry is a Physical
Science
Chemistry is a Physical
Science
A chemical is any substance that has a definite composition.
Definite composition means that a chemical has the same
number of atoms for one molecule of a substance. Water is H2O.
Water is a chemical. One molecule of water has exactly 2 atoms
of hydrogen and one atom of oxygen per molecule of substance.
Chemistry is a Physical
Science
HOMEWORK
For your HW, you will need to be able to identify and define three
different types of scientific research: 1) basic research; 2) applied
research; 3) technological development.
On HW assignments, please always be thorough and accurate. Most
questions on your section reviews will require you to give your
response(s) in complete sentence form. HW grades are scored on
accuracy – therefore, if you do not provide enough information to
adequately answer a question, you will not receive full credit. If you
ever have questions or need clarification, please do NOT hesitate to
ask me!
Chemistry is a Physical
Science
EXAMPLE
1. Compare/Contrast basic research, applied research and
technological development.
ANSWER
1. Basic research is conducted for the sake of knowledge only and
not to meet practical goals. Applied research is conducted to meet
goals defined by specific needs. Technology employs existing
knowledge to make life easier or more convenient.
Matter & its Properties
What is volume?
Mass is a measure of the amount of ________ a substance has.
What is matter?
What are the 2 fundamental building blocks of matter?
An atom is the smallest unit of a(n) __________ that maintains the
chemical identity of that _________.
__ ____________ is a pure substance that cannot be broken down into
simpler, stable substances and is made of one type of atom.
Can a compound be broken down into simpler substances?
Compounds are made of atoms of two ore more elements that are
______________________.
Matter & its Properties
Matter & its Properties
Comparisons of several properties of an unknown substance can
be used to establish its identity.
Properties can be extensive or intensive.
EXTENSIVE PROPERTIES include:
Volume
Mass
Energy quantity
Defined: depend on the amount of matter present.
A chemistry student takes a sample of substance to a digital scale in
the lab. Her sample is found to weigh 2.56 g. Which extensive
property does her measurement represent?
Another student has a solid block of substance and measures its
length, width and height with a ruler using centimeters (cm). Next
he multiplies these three measurements for a product of 4.56 cm3.
Which extensive property does his measurement represent?
Matter & its Properties
INTENSIVE PROPERTIES include:
Melting point
Boiling point
Density
Conductivity ((?))
Defined: do not depend on the amount of matter present. They are
the same for a given substance regardless of how much substance is
present.
Another chemistry student tests the melting point of 2.45 g of a
solid substance and compares its melting point to 5.67 g of the same
solid substance. Will they have the same melting points?
Next, she measures heat conductivity of both substances of varying
masses. Will they have the same amount of conductivity?
Matter & its Properties
Physical properties can be observed/measured _________ changing the
identity of substance. A physical change occurs when the ________ of
the substance is not changed.
Chemical properties are a substance’s ability to undergo changes that
_________ it into different substances. A chemical change (chemical
reaction) is when one or more substances are __________ into
different substances.
Solids have definite _______ & _________. What is an example?
Liquids have definite volume but no definite ________ because they
take the shape of their containers. What is an example?
Gases have no definite _______ or ________. What is an example?
Liquids and gases, because they take the shape of their containers are
known as _________.
Matter & its Properties
Substances that react in a chemical change are called reactants.
HCl + NaOH  NaCl + H2O
Substances that are formed by the chemical change are called
products.
HCl + NaOH  NaCl + H2O
Energy is always involved when physical or chemical changes occur.
Consider ice melting. What type of change of state has occurred?
(physical or chemical).
When wood burns to ash, what type of change of state has
occurred? (physical or chemical).
What do both of these changes have in common?
Matter & its Properties
Matter & its Properties
HOMEWORK
For your homework assignment, you will need to be
familiar with the definitions: mixture, homogeneous
solutions, heterogeneous solutions & pure substances.
Additionally, you will need to be able to compare and
contrast these types of matter. Also, for your upcoming
unit test, be sure you can give an example of each of the
above types of substances.
Elements
…are pure substances that cannot be decomposed by
_______________.
The periodic table is an organization of ___________.
Vertical columns of the periodic table are called _______. (they are also
called families but we will refer to them as the answer for your blank).
Horizontal rows on the table are called ________.
Metals have what 3 properties listed by your textbook?
The ability to be hammered or rolled into sheets is called
_____________.
The ability to be drawn into thin wire is called __________.
The ability to resist breaking when pulled is called __________.
Most metals are solid at room temperature. What is an example of a
metal that is NOT solid at room temperature? Why is this unique
physical property important to us?
Elements
Elements
Most nonmetals are gases at room temperature: N, O, F and Cl.
Others are solid at room temperature: C, P, Se, S & I. Br
(bromine) is liquid at room temperature.
Metalloids have properties of both metals and non metals. They
are ALL solid at room temperature. They are semiconductors of
electricity which makes them useful in current technological
devices such as computers, digital watches and radios.
Elements
What do you know about noble gases?
Do they have a full outer electron shell?
Do they have a filled or “satisfied” octet?
Are they reactive with other elements?
Why or why not?
Can you identify the noble gases on a periodic table?
What is your favorite noble gas?
Why is this your favorite noble gas?
What is the group number for the noble gases?
What is another name for “noble gas”?