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Name:_____________________________________________________________
Period:_________
Unit 2: Matter and Change
Unit Objectives:
 Classify types of matter
 Draw particle diagrams to represent different types of matter
 Recognize various techniques that can be used to separate matter
 Describe changes of state
 Describe basic chemical reactions
Unit Vocabulary:

Matter

Element

Compound

Mixture

Heterogeneous Mixture

Homogeneous Mixture

Pure Substance

Particle Diagram

Chromatography

Filtration

Distillation
1
Date:______
Matter
Do Now: Complete the following Pre-test. Put T for true statements and F for false statements in the
space provided.
____1. Matter is anything that has mass.
____2. A spaceship ceases to be matter when it is in space because it has no weight.
____3. Air can be weighed.
____4. Heat has weight.
____5. Both air and heat are matter.
____6. Matter takes up space.
____7. Air occupies space.
____8. Light takes up space.
____9. Light is matter.
____10. Matter can be in different shapes.
____ 11. Matter can be in different phases.
____12. Water has no definite shape therefore it is not a matter.
____13. A solid has a definite shape.
____14. You cannot change the shape of a solid.
____15. You can compress water to force it to occupy less space.
____16. A glass is inverted over a basin of water and slowly inserted into the water. However,
the water does not enter the glass. This experiment proves that air takes up space.
____17. Air will expand to fill the space available.
____18. Matter can exist in three states: solid, liquid and gas.
____19. Iron combines with oxygen in moist air to form iron oxide, or rust. This change is
called a chemical change.
____20. When water changes to steam it undergoes a chemical change.
2
Matter vs. Not Matter
Can you recognize matter when you see it? What makes matter different from that which is not matter? A
light bulb, for example, is matter. The electricity that makes it glow is not. What is the difference? All
matter has certain characteristics in common that separate it from whatever is not matter. Can you tell
which is which? Get together with your lab group and try. You will be given a card with a list of six items.
Three are matter and three are not.
1. Try to classify the items on the card properly. Write your conclusions in the table below.
MATTER
NOT MATTER
2. Describe the characteristics all the items you classified as MATTER have in common that make
them different from the items you classified as NOT MATTER.
_________________________________________________________________________________________________________________________
Matter- Anything that has mass and volume (takes up space)
1. An element is the simplest form of matter.
• It cannot be decomposed
• Elements are made up of tiny particles called atoms
• There are 7 diatomic elements
2. A compound is a substance made up of two or more elements in a fixed proportion
• compounds are made up of particles called molecules
3. A mixture is a combination of two or more substances (elements or compounds)
• It can be separated into components by physical methods
• It can be homogeneous or heterogeneous
3
Matter
Anything that has mass and
volume (takes up space)
CAN be Separated by
PHYSICAL means
Can NOT be separated
by physical means
MIXTURES (each piece is
different – not pure)
PURE SUBSTANCES
(each piece looks the same
– PURE!)
-each piece has exact same
composition.
Can NOT be separated
by chemical means
ELEMENT (simplest
form of matter)
Example: Na, Cl2
Same
Separated by
composition
chemical means,
throughout
only
Different
composition
throughout
COMPOUND or
MOLECULE
(2+ different elements
chemically combined)
HOMOGENEOUS
MIXTURE (uniform
throughout—distinct
pattern)
HETEROGENEOUS
MIXTURE (not
uniform throughout—
a pattern)
Example: NaCl (table
salt), H2O (water)
Example: saltwater,
iced tea
Example: Italian
dressing, concrete, soil,
chocolate chip cookie
Homo = same
Hetero = opposite
Particle
Diagram
Particle
Diagram
Particle
Diagram
4
Particle
Diagram
Matter Activity
Item
Observations
Element, Compound or
Mixture?
1
2
3
4
5
6
7
8
9
10
11
12
13
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Questions:
1. How could you tell a substance is an element?
2. What phases can elements be in?
3. How could you tell a substance is a compound?
4. What phases can compounds be in?
5. How could you tell a sample is a mixture?
6. What phases can mixtures be in?
5
Defend your answer
Elements, Compounds, and Mixtures
There are 2 types of PURE SUBSTANCES. They can be either an element or a compound.
1.) Element: It is the simplest form of matter that can exist under lab conditions.

Elements cannot be separated into simpler substances.

They are represented by a symbol; ONE Capital Letter. (Each capial letter represents one
element.) Sometimes a lowercase letter is used as well.

Elements are shown on the Periodic Table

There are only 92 naturally-occurring elements. EXAMPLES: Br, Ag, O, N, H etc.
•
There are some elements (only 7!) that exist in nature only as diatomic elements.
Br2, I2, N2, Cl2, H2, O2, F2

That means there are two atoms of one kind stuck (bonded) together so you should always use a
co-efficient of 2 when you see them in an equation!

Here are two examples of particle diagrams that would represent diatomic elements:
2.) Compound: Two or more elements chemically combined with each other.
 Compounds can be separated into simpler substances.

A compound has a fixed composition. It is always the same.

Formulas for compounds are written in a certain way.
EXAMPLES: H2O
CO2
NaCl
 The little numbers directly following an element symbol are called subscripts.
This tells you how many atoms of that element are in the compound.


EXAMPLES: H2O
CO2
NaCl
(2 H’s and 1 O)
(1 C and 2 O’s) (1 Na and 1 Cl)
A common mistake by students such as yourself happens in compounds like CO2. The 2 goes ONLY
TO THE O… NOT TO THE C (as shown above in the formula and below in the picture.)
We can draw particle diagrams of these three compounds as follows:
H2O

CO2
NaCl
Compounds are made up of molecules (a specific ratio of chemically combined atoms).
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A mixture is a blend (physical change) of two or more substances.

Homogeneous Mixtures are uniform throughout
Examples: salt in water, air

Heterogeneous Mixtures are non-uniform
Examples: chunky chicken soup, dirt in water
Homogeneous and Heterogeneous are both relative terms. This means that some of your answers will
depend on your prior experiences and knowledge. As long as you can defend/explain why you answered
your question the way you did, it is acceptable.
Na + S is a mixture.
Likewise Na2S + KCl is a mixture
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Matter Practice
Directions: After each statement below, choose the letter of the word that applies from the list below.
a. matter
b. substance
c. mixture
d. element
e. compound
f. heterogeneous mixture
g. homogeneous mixture
_____ 1) cannot be chemically decomposed
_____2) components can be combined in any ratio
_____ 3) components must be combined in a specific, fixed ratio that can never change
_____ 4) has mass and volume
_____5) chemically combined to produce new substance with totally new properties
_____ 6) substances are physically combined, unevenly spread throughout
_____7) substances are physically combined, evenly spread throughout
_____ 8) combining substances where each substance retains its individual properties
_____ 9) manganese
_____ 10) Al2(SO4)3
_____ 11) sand in water
_____ 12) physically combined, physically separated
_____ 13) since the substances retain their individual properties, they can be separated based on their
unique physical properties
_____ 14) can’t be physically decomposed, but can be chemically decomposed
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Separating Mixtures
Since mixtures are made by physically combining 2 or more pure substances together, we use physical
techniques to separate them. The technique used depends on what phase or state of matter the
components are.
1.
2.
3.
4.
5.
Fitration-solid and a liquid
Phase change-distillation, evaporation, etc.
Separatory funnel-two immiscible liquids
Various physical means such as magnet, tweezers, sieve -two solids
Chromatography – density and particle size differences
Separation Apparatus
Type of Separation
(Physical or Chemical)
Filtration
PHYSICAL
Watch Glass Evaporation
PHYSICAL
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Description of
Technique
Undissolved
particles
remain on
filter paper
(filtrate flows
through filter
paper)
 Separate
solute
(dissolved
solid) from
solvent
(liquid) by
boiling
solution
 Solute
escapes
 Very limited
precision
What types of
Matter will it separate?
HETEROGENEOUS
mixtures (ex: sand
water)
*Can also centrifuge
HOMOGENEOUS mixture
(solution)
Distillation
PHYSICAL
 Separate solute
from solvent by
boiling solution
and
recondensing in
receiving flask
(both solute and
solvent
captured)
HOMOGENEOUS (can
use to remove
impurities from
water)
 Separate 2 or
more liquids
with different
boiling points
Chromatography
PHYSICAL
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Separates
particles based
on:
1) size
2) solubility
HOMOGENEOUS
Check your Understanding:
For each picture below:
a) Identify the separation technique from the list above.
b) Select the property that allows for the technique to work, from among these choices:
1. Differences in particle “attractiveness” or “electrical stickiness” of the mixture components,
allowing them to be separated when solvent and some other medium (like paper)
“compete” for the mixture components.
2. Differences in particle size of the mixture components.
3. Differences in particle boiling points of the mixture components.
Technique: ___________
Property allowing it to work: # ___
Technique: ________________
Technique:______________
Property allowing it to work: # ____
Property allowing it to work: #____
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Particle Diagrams of Matter
Particle diagrams are used to illustrate states and forms of matter. Typically, a particular type of atom is
shown as a small circle of one color or shade.

A diagram of an element would contain only one type of atom.

A compound would contain two or more types of atoms attached in a fixed ratio

A mixture would contain one or more elements and one or more compounds.
Check your understanding:
IDENTIFY THE FOLLOWING AS A PURE ELEMENT, PURE COMPOUND OR MIXTURE OF ???
___________
__________
____________
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__________
__________
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Check your Understanding:
1. Two substances, A and Z, are to be identified. Substance A can not be broken down by a chemical
change. Substance Z can be broken down by a chemical change. What can be concluded about these
substances?
a. Both substances are elements.
b. Substance A is an element and substance Z is a compound.
c. Both substances are compounds.
d. Substance A is a compound and substance Z is an element.
2. Base your answer to the question on the information below.
The particle diagrams below represent the reaction between two nonmetals, A2 and Q2
Using the symbols A and Q, the chemical formula of the product could be written as
a) AQ
b) A2Q
c) AQ2
d) A2Q2
3. Which statement describes a chemical property of oxygen?
a)
b)
c)
d)
Oxygen has a melting point of 55 K.
Oxygen gas is slightly soluble in water.
Oxygen can combine with a metal to produce a compound.
Oxygen gas can be compressed.
4. Which two substances can not be broken down by chemical change?
a) C and CuO
b) CO2 and CuO
c) C and Cu
d) CO2 and Cu
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5. Which particle diagram represents one pure substance, only?
6. Which substance can be decomposed by chemical change?
a) beryllium
b) methanol
c) boron
d) magnesium
7. Which species represents a chemical compound?
a) N2
b) Na
c) NH +
d) 4. NaHCO3
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Phase Changes
Directions:Using the diagram above as a reference, draw a particle diagram for a solid, liquid, and
gas of the same substance.Use at least 6 particles. Also, identify the changes in the states of
matter (as represented by the arrows between states).
SOLID (s)
LIQUID (l)
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GAS (g)
Almost all substances can be made to change between the 3 phases, simply by altering the temp.
The classification of matter into solids, liquids and gases is termed as physical classification of
matter.
Characteristics of solids
1. Solids maintain their volume independent of the size or shape of the container in which they are
placed in.
2. Solids are rigid and have definite shape.
3. Solids diffuse very slowly compared to liquids and gases, due to close packing
4. Solids are incompressible
5. Most solids melt on heating, and some sublimate.
6. Solids have very high mass to volume ratio or density compared to liquid or gases.
Characteristics of liquids



Moderate forces of attraction exist between the molecules of a liquid.
The molecules in a liquid are in a state of random motion although the extent is much smaller in
comparison to gases.
The average Kinetic energy of the molecules in a liquid is proportional to the temperature.
Characteristics of gases





Gases maintain neither volume nor shape and completely fill the container in which they are
introduced.
Gases expand when heated
Gases diffuse rapidly; we can smell perfume even when applied at a distance very fast
Gases are highly compressible; if pressure is increased then volume decreases
Almost all gases except a few are colorless
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Properties
SOLID
LIQUID
SHAPE
(definite, takes
shape of container)
VOLUME
(definite, takes
volume of
container)
PARTICLE
MOVEMENT
(Vibrates, moves
freely)
DENSITY
Distance between
particles
Attraction
between particles
(Strong, Weak)
PARTICLE
DIAGRAM
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GAS
Heating Curve Worksheet
Below is a diagram showing a typical heating/cooling curve for water. It reveals a wealth of information about the
structure and changes occurring in water as it is heated or cooled through all three phases of matter at different
temperatures. At the top of the diagram are pictures representing the typical particle arrangement as substances change
through their states.

Heat removed
1. There is something clearly wrong about the particle spacing in the pictures at the top. What is it? (Hint…
the pictures were drawn for most materials, not for water specifically).
2. Identify by letter (A-E) in which section the following are found:
a. _______ Freezing (if cooling)
b. _______ Particles farthest apart
c. _______ Boiling
d. _______ Particle motion is most restricted
e. _______ Heat of fusion
f. _______ All areas where energy change is potential only
g. _______ Heat of vaporization
h. _______ All areas where particles move past each other
i. _______ Least kinetic energy
j. _______ All areas where kinetic energy is changing
k _______ most potential energy
l. _______ All areas where phase changes occur
m. _______ All areas in which the heat is making the particles move faster
n. _______ All areas in which the heat is breaking the attractions or bonds between particles
o. _______ All areas in which the particles are not changing their speed
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Now try an unlabeled heating curve for water without pictures and see how well you do!
Heating / cooling curve for water

Heat removed
1. First identify the sections where the following phases are found:
a. _______ gas
b. _______ solid
c. _______ liquid
d. _______ solid and liquid
e. _______ liquid and gas
2. Identify by letter (A-E) in which section the following are found:
a. _______ Freezing (if cooling)
b. _______ Particles farthest apart
c. _______ Boiling
d. _______ Particle motion is most restricted
e. _______ Heat of fusion
f. _______ All areas where energy change is potential only
g. _______ Heat of vaporization
h. _______ All areas where particles move past each other
i. _______ Least kinetic energy
j. _______ All areas where kinetic energy is changing
k _______ most potential energy
l. _______ All areas where phase changes occur
m. _______ All areas in which the heat is making the particles move faster
n. _______ All areas in which the heat is breaking the attractions or bonds between particles
o. _______ All areas in which the particles are not changing their speed
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Physical and Chemical Properties
Do Now: Read the following and fill in the information:
Physical
Chemical
Properties of Matter
Observable or measurable porperties
Ex) hardness, color, smell, mass, melting point
Describes how a substance reacts OR does not react with
other substance(s)
Ex) Copper reacts with Nitric Acid, Cu does not react with
hydrochloric acid (HCl)
Identify the following as being physical or chemical properties.
________________1. The mass of copper wire is 255 g.
________________2. The boiling point of ethyl alcohol is 77°C.
________________3. Baking soda reacts with vinegar to make carbon dioxide gas.
________________4. The density of mercury is 13.6g/mL.
________________5. The solubility of sodium chloride in water is 40g/100mL of water.
Physical and Chemical Changes
Physical
Chemical
Properties of Matter
Observable or measurable properties
Ex) hardness, color, smell, mass, melting
pt.
Describes how a substance reacts OR does
not react with other substance(s)
Ex) Copper reacts with Nitric Acid, Cu does
not react with hydrochloric acid (HCl)
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Changes in Matter
Altering a substance without changing its
composition or properties; the original
material can be recovered.
(Still the same substance but in a different
form)
A new substance is made that has a different
composition and properties; the original
material can sometimes (not usually) be
recovered, but usually only with great
difficulty.
(New substanced formed)
Reactions
In order to keep track of how things are changing. We have to look at the before and the after. Chemists
do this by writing an equation, similar to what you have done in math class. The only real difference, is
that you replace the = with !
Some important vocab:
 An equation describes a chemical change or reaction. The equation shows substances which react
with each other once mixed to form other substances.
 Reactants (the substances that we start with, or in other words that react) are on the left side of
the equation.
 Products (the substances that we end with, or in other words are produced) are on the right side
of the equation.
 Reactants and products are separated by an arrow. It shows the direction of the equation.
 System is another word for reaction that is often used by chemists.
For example:
I am starting with Na and Cl and I want to change it into NaCl. We can do a reaction to make this happen
and we can record the change with an equation.
2Na
+
Cl2

2 NaCl + heat
1) How many different substances are described on the “left side” of the equation?
2) How many different substances described on the “right side” of the equation?
3) What does this tell me? I can look at an equation to see if a change is chemical or physical. In this
case, since a new substance is formed, it is a chemical change.
***Note that the number and kind of atoms on the left side of the equation equal the number and kind of
atoms on the right side of the equation. Only the arrangement of the atoms has changed in going from
reactants to products.
The equality of atoms or matter on either side of a chemical equation is called a balanced equation; it
illustrates the principle of the Conservation of Matter.
Conservation of Matter: Matter can neither be created or destroyed , but the atoms in the reactants can
become rearranged in a chemical change. Weighing the system before and after a chemical change
is a way to prove this.
Note: Conservation of Matter is also called Conservation of Mass. They are interchangable terms. To
see if an equation has conservation of matter or mass, we look for the one that is balanced.
For example:
Pick the change (equation) that correctly shows a conservation of mass:
1) NaCl  Na + 2 Cl
2) 2 NaCl  2 Na + Cl
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3) NaCl  2 Na + Cl2
4) 2 NaCl  2 Na + Cl2
Conservation of Energy...Exo vs. Endothermic Changes (Reactions)
Just as there is a Law of Conservation of Matter, there is a Law of Conservation of Energy.
Law of Conservation of Energy- Energy can neither be created or destroyed.
Usually there is an energy change involved in either a chemical change or a physical change.
Reaction
How I Know
Direction of
Heat Flow
Type of Energy
Change
Requires
Heat
Feels cold
around the
change
Feels hot
around the
change
From the
surroundings
into the system
From the
system into the
surroundings
Endothermic
Reactant or
Product (in
Equation)
Reactant
Exothermic
Product
Releases
Heat
Check your understanding:
State whether the following reactions or processes are physical or chemical changes and if they are
exothermic or endothermic:
1. Burning charcoal glows bright red until it turns to ash
2. To convert one gram of ice to water, 334 J of heat must be added.
3. SO3(g) + H2O (l)  H2SO4(aq) + heat
4. CaCO3(s) + heat  CaO(s) + CO2(g)
5. Neutralization of a strong acid with a base gives a warm solution.
6. Barium hydroxide mixed with ammonium chloride yields ammonia
gas and the flask gets cold.
7. When heated to a high temperature, iron melts.
8. Water freezes to ice at 0 degrees Celsius.
23
Changes Written as Equations
Do Now: Complete the chart to the best of your ability.
Situation
Type of Change (P
or C)
Cooking an egg
Digesting your
lunch
Mixing the
ingredients for a
cake
Rusting of a nail
Dew forming on the
lawn
Melting ice off a
windshield
Combustion
(burning) of
gasoline
Purifying salt water
by evaporation
CO2 (s)  CO2 (g)
H2O (g)  H2O (l)
H2O
NaCl (s)  NaCl
(aq)
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Explanation (Write a sentence.)
Unit 2 Matter: General Chemistry Review
ELEMENTS, COMPOUNDS, AND MIXTURES
1. Matter is anything that has a mass and takes up space. An element is the simplest form of matter which
cannot be broken down any further. Elements are listed on Table S and the periodic table. Their symbols start
with an uppercase letter.
a. Which of the following is not matter? _____________________
Magnesium
Calcium Carbonate
Salt water
Heat
b. Which of the above is an element? _____________________
2. Compounds are composed of two or more elements. They can only be decomposed chemically. Elements
and compounds are also known as substances.
a. Which of the choices in number one was a compound? ________________________
b. How can compound be broken down? __________________________________________________
c. Which of the choices in question one are substances? ______________________________________
3. Mixtures are physical combinations of two or more substances (elements and/or compounds). Mixtures can
be homogeneous (completely mixed, cannot see the parts) or heterogeneous (unevenly mixed, can see the
parts). Mixtures can be separated by physical means.
a. Label each as homogeneous or heterogeneous:
Sand: ____________________
Brass: ______________________________
Milk: ____________________
Oil and water: ________________________
4. Compounds must be separated chemically but mixtures can be separated easily using physical methods.
a. Match each method with its name.
Distillation
Separated by differences in particle size
Filtration
To pour off the top layer of an uneven mixture
Decant
Separated by differences in boiling point.
b. Which of the above processes only work if the mixture is heterogeneous? _____________________
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c. Label the following as element (E), compound (C), or mixture (M).
__________________________________________________________________________________________
SOLIDS, LIQUIDS, AND GASES
5. A solid has a definite shape and volume. Solids are arranged in a geometric pattern. Liquids have a definite
volume but take the shape of the container they are in. Gases have an indefinite shape and volume; they take
the shape and volume of the container. Gases are easily compressed.
a. Draw particle diagrams for a solid, liquid, and a gas using at least 5 particles:
b. Which has a definite shape?
HCl(g)
H2O(l)
Cu(s)
c. Which has a definite volume?
LiF(g)
Br2(l)
Mg(s)
6. Vapors are the gas phase of substances that are normally solid or liquid at room temperature.
a. Which can be a vapor?
Carbon dioxide ______
Water _____
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Oxygen _____
__________________________________________________________________________________________
CHANGES IN THE LAB
7. Physical changes are changes where the substance retains its properties. Chemical changes will make
substances change into new substances and change properties.
a. Label the following as physical (P) or chemical (C) properties:
Texture
Odor
____
____
flammability ____
boiling point:
____
color
chemical composition:
____
____
b. Label the following as physical (P) or chemical (C) changes:
Corrosion: ____
melting:
____
mixing:
____
Freezing: ____
cutting:
____
decaying:
____
8. In chemical reactions mass is conserved.
a. Can you form or destroy matter? _______________________________________________________
b. Mass of reactants is ______________ mass of products. (Greater than, Equal to, or less than?)
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