[Chapter One: The Science of Chemistry ] [2010]
Chapter One
The Science of Chemistry
PHYSICAL VS. CHEMICAL PROPERTIES
A physical property is observed with the senses and can be determined without destroying the
object. For example, color, shape, mass, length and odor are all examples of physical properties.
A chemical property indicates how a substance reacts with something else. The original substance
is fundamentally changed in observing a chemical property. For example, the ability of iron to rust
is a chemical property. The iron has reacted with oxygen, and the original iron metal is changed. It
now exists as iron oxide, a different substance.
Classify the following properties as either chemical or physical by putting a check in the appropriate
column.
Physical Property
Chemical Property
Blue color
Density
Flammability
Solubility (Dissolve)
Reacts with acid to form
hydrogen
Color changes from blue
to red
Supports combustion
Melting point
Reacts with water to
form gas
Reacts with a base to
form water
Smells bad as it sours
Hardness (does it break
easily?)
Boiling point
Can neutralize a base
Luster (shiny?)
Smells like lemons
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[Chapter One: The Science of Chemistry ] [2010]
PHYSICAL VS. CHEMICAL CHANGES
In a physical change, the original substance still exists. It has only changes in
form. In a chemical change, a new substance is produced. Energy changes
always accompany chemical changes.
Classify the following as being a physical or chemical change and circle the
clue word(s) .
1. Sodium hydroxide dissolves in water.
2. Hydrochloric acid reacts with potassium hydroxide to produce a salt, water
and heat.
3. A pellet of sodium is sliced in two.
4. Water is heated and changed to steam
5. Potassium chlorate decomposes to potassium chloride and oxygen gas.
6. Iron rusts to form iron oxide.
7. When placed in H2O, a sodium pellet catches on fire as hydrogen gas is
liberated and sodium hydroxide is formed.
8. Evaporation
9. Ice melting
10. Milk sours
11. Sugar dissolves in water.
12. Wood rotting
13. Pancakes cooking on a griddle
14. Grass growing in a lawn
15. A tire is inflated with air.
16. Food is digested in the stomach.
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Concept
Definition
Map
[Chapter One:
The Science
of Chemistry
] [2010]
Book Definition
Broader Category
KEY VERBS
What to look for to
rule it in
Physical
Change
EXAMPLE/TYPE 1
EXAMPLE/TYPE 2
What to look for to rule it
out
EXAMPLE/TYPE 3
3
Concept
[Chapter One: The
ScienceDefinition
of Chemistry Map
] [2010]
Book Definition
Broader Category
KEY VERBS
What to look for to
rule it in
Chemical
Change
4 Signs:
1.
2.
3.
4.
EXAMPLE/TYPE 1
EXAMPLE/TYPE 2
What to look for to rule it
out
EXAMPLE/TYPE 3
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[Chapter One: The Science of Chemistry ] [2010]
CLASSIFICATION ACTIVITY I
Consider the list of substances below.
Step 1: Your job is to group these substances into four categories based on similarities and
differences. You must use five categories. No more and no less.
Step 2: Write a brief description for each category, explaining how you decided what belongs in
that category.
Step 3: Come up with an appropriate title or name for each category.
Paint
Mercury
Water
Air
Italian Dressing
Baking Soda
Iron
Sand in Water
Milk
Jello
Tap Water
Rust (Fe2O3)
Sugar Water
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[Chapter One: The Science of Chemistry ] [2010]
SECTION 3 HOW IS MATTER CLASSIFIED? Pg. 21 - 28
Construct the following flow chart as work through the reading. Each unattached box is provided so that you can fill in a brief definition
Types of Matter
Matter
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Types of
Matter
Semantic
Map
Can be separated by density
Can be separated through boiling
Created through physical means
Differences can be seen with the
naked eye
Created through a chemical
reaction
Can be separated through filtration
Can be separated through physical
means
Can be separated through chemical
means
Mixture
Pure
Contains 2 or more elements in a
definite ratio
Contains 2 or more elements in
which the amount can vary
Contains only one type of atom
[Chapter One: The Science of Chemistry ] [2010]
SEMANTIC MAP: TYPES OF MATTER
Element
Compound
Heterogeneous
Mixture
Homogeneous
Mixture
Solution
Suspension
Colloid
Define the following terms:
Element:
Compound:
Heterogeneous Mixture:
Homogeneous Mixture:
Solution:
Suspension:
Collloid:
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[Chapter One: The Science of Chemistry ] [2010]
PRACTICING THE METRIC SYSTEM
Convert the following from the given unit to the requested unit:
1)
360 g to
mg
12)
18.05 m to
cm
2)
0.00238 cg to
g
13)
3.80 km to
m
3)
13.52 g to
kg
14)
14.28 m to
km
4)
0.014 kg to
cg
15)
35.85 cm to
km
5)
43.25 cg to
mg
16)
40.6 dm to
mm
6)
641.5 mg to
g
17)
1.05 mm to
cm
7)
281 ml to
l
18)
8.75 mm to
8)
4.305 l to
ml
9)
28.5 ml to
l
10)
1.832 L to
ml
11)
6.58 cm to
mm
____________
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[Chapter One: The Science of Chemistry ] [2010]
DENSITY PROBLEMS
Be sure to include units in all answers.
Reminders:
1cm3 =1mL
Density = Mass  Volume
1. What is the density of a material if its mass is 2.02 g and its volume is .500cm3? (4.04)
2. What is the density a substance that has a mass of 87.6g and a volume of 8.09cm 3?
3. A substance has a mass of 61.9g and its volume is 5.46cm3, what is this density? (11.3)
4. What's the density of a sample that has a mass of 75.4g and a volume of 5.24cm3?
5. What is the density of a material when the mass is 20.4g and the volume is 18.6cm3?
(1.10)
6. A sample has a volume of 10.2cm3 and a mass of 15.6g. What is the density of the gold?
7. A sample has a mass of 1.02g and a volume of 1.35cm3, what is the density of the nickel?
(0.75)
8. What is the density of a substance that has a mass of 54.2g and a volume of 3.06cm 3?
9. What is the density of a substance when its volume is 51.6cm3 and its mass is 134.5g?
(2.6)
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[Chapter One: The Science of Chemistry ] [2010]
MORE DENSITY PROBLEMS
1. What is the volume of a 898 kilogram piece of iron metal (density is 7.75 g/mL)?(115,871)
2. Calculate the mass of a liquid with a density of 3.2 g/mL and a volume of 25 mL.
3. An irregular object with a mass of 18 kg displaces 2.5 L of water when placed in a large
overflow container. Calculate the density of the object. (7.2)
4. A graduated cylinder has a mass of 80 g when empty. When 20 mL of water is added, the
graduated cylinder has a mass of 100 g. If a stone is added to the graduated cylinder, the
water level rises to 45 mL and the total mass is now 156 g. What is the density of the
stone?
5. An object has a mass of 49 kilograms and a volume of 93.2 ml. What is the density? (0.53)
6. If object has a density of 1.12 g/ml and a mass of 96 g. What volume does it occupy?
7. The volume of an object is 492 ml. Its mass is 675 grams. What is the density of this object?
(1.37)
8. If an object has a volume of 100 cm3 and a density of 2.92 g/cm3, what is its mass?
9. An object is placed in a graduated cylinder which previously held 20.0 ml of water. The water level
rose to 39.5 ml. After removing the object and drying it, the student placed the object on the
balance, which read 203 grams. What is the density of this object? (10.4)
10. Calculate the mass of an object, which has a volume of 125 ml and a density of 9.5 g/ml.
11. An empty beaker weighs 243 grams. A liquid is added to the beaker and the mass increases to
493 grams. Calculate the volume of the liquid if the density is 0.70 g/ml. (357)
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[Chapter One: The Science of Chemistry ] [2010]
Density Worksheet
1. Define mass?
2. Define volume?
3. Define density and show the formula for calculating density.
4. Why does changing the shape of an object have no effect on the density of that
object?
5. Aluminum is used to make airplanes. Cast iron is used to make weightlifting
equipment. Explain why the densities of these metals make them useful for these
purposes?
6. Calculate the densities of the following objects. Remember to place units after
each number.
Object A length = 6cm width = 3cm height = 1cm mass = 36g
volume = ___________ density = ___________
Object B length = 10cm width = 5cm height = 2cm mass = 300g
volume = ___________ density = _____________
Object C Use the water displacement method to determine the density of object C (silly
putty).
initial water level in graduated cylinder = 25ml
final water level after placing silly putty into graduated cylinder = 29ml
mass of silly putty=8g
volume = ____________ density = ___________
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[Chapter One: The Science of Chemistry ] [2010]
TOPIC: ____________________________________
K(now): List what you already know
W(onder): List what you wonder about or want to
know
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[Chapter One: The Science of Chemistry ] [2010]
L(earned): Write two (2) sentences about what you have
learned.
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[Chapter One: The Science of Chemistry ] [2010]
Anticipation Guide for Section 1: What is Chemistry
Page 4-8
Before reading: In the space to the left of each statement, place a check mark () if you agree or
think the statement is true.
During or after reading: Add new check marks or cross through those about which you have
changed your mind. Keep in mind that this is not like the traditional “worksheet.” You may have to
put on your thinking caps and “read between the lines.” Use the space under each statement to
note the page, column, and paragraph(s) where you are finding information to support your
thinking.
___ 1. Soap is a type of chemical that we use everyday.
___ 2. An example of a chemical reaction is when water is put in the freezer to make ice cubes.
___ 3. The particles in a solid are not moving and are all touching each other.
___ 4. An example of a physical change would be ripping a piece of paper in half.
___ 5. Burning a piece of magnesium would be an example of a chemical change.
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[Chapter One: The Science of Chemistry ] [2010]
States of Matter
1. Particles in the solid ice cube appeared to move while staying within their rigidly
defined positions. These particles have_____________________ motion only.
2. From what you observed, applying pressure to a liquid causes its molecules to move
____________________ . If enough pressure is applied, the liquid becomes a(n)
__________________.
3. ______ Solids have the following properties with oneexception. Choose the property that
does not apply to a solid.
a. definite shape
c. orderly arrangement of particles
b. easy to compress
d. definite volume
4. Explain why ice is an example of a solid.
5. Hexane is a liquid. Explain why hexane is also a fluid.
6. How do the shapes and sizes of the graduated cylinder, Erlenmeyer flask, and
measuring cup affect the volume of the 50 mL hexane sample? How does the size of a container
affect the volume of a gas?
Worksheet 1.1
7. Compare and contrast particle motion for the three states of matter using the particle
views in Sections a through c as examples.
8. What happens to the motion of gas particles when they are compressed by a piston?
9. List three of the properties of a liquid.
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MODULE 2
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