What is
Chemistry?
Chemistry is…
The study of all substances and
the changes they undergo,
central science because it
overlaps many other sciences
Who Uses Chemistry?
Who Uses Chemistry?
If you think the answer consists of
a variety of scientists, you have a
lot to learn. 
Who Uses Chemistry?
These people all use chemistry on
a daily basis…
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Forensic examiners
Perfume makers
Dye makers
Medical researchers
Engineers
Biologists
Agriculture workers
Artists
Archaeologists
Ecologists
Waste water treatment workers
Cooks
Textile manufacturers
Beauticians
And many more…
Lab Equipment
Goggles
Goggles are meant to protect your eyes and
therefore need to be worn appropriately. If you wear
glasses, you still need to wear goggles.
Beaker
Beakers hold solids or liquids that will not release
gases when reacted or are unlikely to splatter if
stirred or heated.
Graduated Cylinder
A graduated cylinder is used to measure
volumes of liquids. This is a better choice
for measuring volume than beakers or
flasks.
Erlenmeyer Flask
Erlenmeyer flasks hold solids or liquids that may release
gases during a reaction or that are likely to splatter if
stirred or heated.
Weighing Boat
Weighing boats are used to weigh solids that will be transferred
to another vessel.
Test Tube Racks
Test tube racks are for holding and organizing test tubes on the laboratory counter.
Test
Tubes
13 x 100 mm test tubes
Ignition
tube
10 x 75 mm test tubes
A test tube is useful for holding liquids and for
containing small chemical reactions.
Test Tube Holder
A test tube holder is useful for holding a test
tube which is too hot to handle.
Beaker Tongs
Beaker tongs are used to move beakers
containing hot liquids
Crucible Tongs
For handling hot crucibles; also used to pick up other hot
objects. NOT to be used for picking up beakers!
Test Tube Brushes
Test tube brushes are used to clean test tubes and
graduated cylinders.
Forcing a large brush into a small test tube will often break
the tube.
Rubber Stoppers
Rubber stoppers are used to close containers to avoid
spillage or contamination.
Containers should never be heated when there is a stopper
in place.
Spot Plates/Well Plates
Spot plates are used when we want to perform many small
scale reactions at one time.
Glass Stir Rod
A glass rod is used to manually stir solutions.
Medicine Dropper
A medicine dropper is used to transfer a small
volume of liquid (less than one mL). In class, we
often use disposable pipettes instead of droppers.
Litmus
Paper
Red litmus paper is used to identify bases.
Blue litmus paper is used to identify acids.
Forceps
Forceps (or tweezers) are used to pick up small objects.
Funnel
A funnel is used to aid in the transfer of
liquid from one vessel to another.
Wash Bottle
A wash bottle has a spout that delivers a wash solution
to a specific area. Distilled water is the only liquid that
should be used in a wash bottle.
Spatulas
Spatulas are used to dispense solid chemicals from their
containers.
Chemicals should never be transferred with your bare
hands.
Scoopulas
Scoopulas are used to dispense solid chemicals from
their containers.
Chemicals should never be transferred with your bare
hands.
Strikers
Strikers are used to light Bunsen burners.
The flints on strikers are expensive. Do not operate the
striker repeatedly just to see the sparks!
Bunsen Burner
Bunsen burners are used for the heating of nonvolatile
liquids and solids.
Crucible
Crucibles are used for heating certain solids, to very
high temperatures.
Clay Triangle
The clay triangle is used as a support for porcelein
crucibles when being heated over a Bunsen burner.
Ring stands and their
Components
Ring stands are a safe and convenient way to perform reactions that
require heating using a Bunsen burner.
Ring stands and their
Components
Iron Rings
Iron rings connect to a ringstand and provide a stable,
elevated platform for the reaction.
Ringstands and their
Components
Utility Clamps
Utility clamps are used to secure test tubes, distillation
columns, and burets to the ringstand.
Ringstands and their
Components
Wire Gauze
Wire gauze sits on the iron ring to provide a place to stand a
beaker.
On older wire gauze, the white material is asbestos!
Lab Issues
Lab Safety
•
•
•
•
Flinn contract
Broken glass bucket
Fire extinguisher
Eye wash
Scientific Notation
Writing
• Format: M x 10x
–M must be less than 10
–M must be greater than or
equal to 1
–x can be any whole number
Scientific Notation
Sample Numbers to Write
• 450
• 3,000,000
• 0.014
• 0.000 000 08
Measurement
Two types of measurements
• Qualitative – present
regardless of amount
Examples – color, taste, luster,
density, etc.
Measurement
Two types of measurements
• Quantitative – based on
amount
Examples – mass, length,
area, volume, etc.
Metric Units
In science, we use the metric
system because it is an
international system (unlike
the English system that is
rarely used). These units have
precise definitions.
Metric Units
SI Base units
• Length – meter, m
• Mass – kilogram, kg
• Time – second, s
• Count – mole, mol
• Temperature – kelvin, K
Sometimes, the base units are
combined to create other units
Measurement
Derived units
•
•
•
•
•
•
•
•
•
Area – square meter, m2
Volume – cubic meter, m3
Force – newton, N
Pressure – pascal, Pa
Energy – joule, J
Power – watt, W
Voltage – volt, V
Frequency – hertz, Hz
Electric charge – coulomb, C
Measurement
Metric Prefixes
Sometimes SI units aren’t
convenient for object being
measured so we use metric
prefixes to indicate smaller or
larger units of measurement.
Measurement
Metric Prefixes
Sometimes SI units aren’t convenient for object being measured so we use
metric prefixes to indicate smaller units of measurement.
• mega
M
1,000,000
1 x 106
• Kilo
k
1,000
1 x 103
• hecto
h
100
1 x 102
• deka
dk
10
1 x 101
• -unit1
1 x 100
• deci
d
0.1
1 x 10-1
• centi
c
0.01
1 x 10-2
• milli
m
0.001
1 x 10-3
• micro
m
0.000,001
1 x 10-6
• nano
n
0.000,000,001
1 x 10-9
• pico
p
0.000,000,000,001
1 x 10-12
Measurement
Metric Prefixes
Sometimes SI units aren’t convenient for object being measured so we use metric prefixes to indicate smaller units of
measurement.
•
mega M
1,000,000
106
•
kilo
k
1,000
103
•
hecto h
100
102
•
deka
dk
10
101
•
-base1
100
•
deci
d
0.1
10-1
•
centi
c
0.01
10-2
•
milli
m
0.001
10-3
•
micro m
0.000,001
10-6
•
nano
n
0.000,000,001
10-9
•
pico
p
0.000,000,000,001
10-12
The symbols for these prefixes can
be added to the beginning of any
SI unit to indicate smaller or
larger measurements.
Precision vs. Accuracy
What is precision?
how well measurements agree
with each other
Example:
3 measurements taken of a
mass give 1.00 g, 1.02 g, &
1.01 g
Precision vs. Accuracy
What is accuracy?
how well measurements agree
with an accepted standard
Example:
3 measurements taken of a
mass give 1.00 g, 1.02 g, &
1.01 g, accepted value =
1.01 g
Percent, Percent Error, Ratios
How to express results…
Percent =
obtained × 100= _%
total
–May be given mixture and
asked to calculate percent of
one part
Percent, Percent Error, Ratios
How to express results…
Percent
Example: A sample is 750 g.
400 g of that 750 g are lead.
What is the percent of lead?
Percent, Percent Error, Ratios
How to express results…
Percent error =
(measured – accepted) × 100
accepted
• Can be + or -, depends on
whether measurement was
more or less than accepted
value
Percent, Percent Error, Ratios
How to express results…
Percent error
Example: An object was measured
45 cm. The actual value was
45.5 cm. What was the percent
error?
Percent, Percent Error, Ratios
How to express results…
Ratio
•
•
•
•
speed = dist/time
Population density = pop/area
Density = m/v
The previous equations may be
rearranged to solve for any of the
variables.
Percent, Percent Error, Ratios
How to express results…
Ratio
•
•
•
•
speed = dist/time
Population density = pop/area
Density = m/v
The previous equations may be rearranged to solve for any of the variables.
• Example 1: Find the density of
iron with mass 1.23 kg and
volume 156 cm3.
Percent, Percent Error, Ratios
How to express results…
Ratio
•
•
•
•
•
speed = dist/time
Population density = pop/area
Density = m/v
The previous equations may be rearranged to solve for any of the variables.
Example 1: Find the density of iron with mass 1.23 kg and volume 156 cm 3.
• Example 2: A liquid has mass
30.6 g and volume 53.3 mL.
What is the density?
Percent, Percent Error, Ratios
How to express results…
Ratio
•
•
•
•
•
•
speed = dist/time
Population density = pop/area
Density = m/v
The previous equations may be rearranged to solve for any of the variables.
Example 1: Find the density of iron with mass 1.23 kg and volume 156 cm 3.
Example 2: A liquid has mass 30.6 g and volume 53.3 mL. What is the density?
• Example 3: Iron has density
3
7.86 g/ cm . Could a metal
block of mass 12.8 g and
3
volume 2.56 cm be iron?
Percent, Percent Error, Ratios
How to express results…
Ratio
•
•
•
•
•
•
•
speed = dist/time
Population density = pop/area
Density = m/v
The previous equations may be rearranged to solve for any of the variables.
Example 1: Find the density of iron with mass 1.23 kg and volume 156 cm 3.
Example 2: A liquid has mass 30.6 g and volume 53.3 mL. What is the density?
Example 3: Iron has density 7.86 g/ cm3. Could a metal block of mass 12.8 g and volume 2.56 cm 3 be iron?
• Example 4: Find mass of 200.
cm3 of air if the density is
3
0.0013 g/cm
Percent, Percent Error, Ratios
How to express results…
Ratio
•
•
•
•
•
•
•
•
speed = dist/time
Population density = pop/area
Density = m/v
The previous equations may be rearranged to solve for any of the variables.
Example 1: Find the density of iron with mass 1.23 kg and volume 156 cm 3.
Example 2: A liquid has mass 30.6 g and volume 53.3 mL. What is the density?
Example 3: Iron has density 7.86 g/ cm3. Could a metal block of mass 12.8 g and volume 2.56 cm 3 be iron?
Example 4: Find mass of 200. cm3 of air if the density is 0.0013 g/cm3
• Example 5: What is the
volume of 160.0 g iron if
density is 7.86 g/cm3
Density
• A copper penny has a mass of 3.1
g and a volume of 0.35 cm3.
What is the density?
Density
• A graduated cylinder contains
44.2 mL of water. A 48.6 g piece
of metal is dropped into the
cylinder and the water rises to the
51.3 mL mark. What is the
density of the metal?
Density
• A plastic ball with a volume of
19.7 cm3 has a mass of 15.8 g.
What is the density? If the
density of gasoline is between
0.66 g/cm3 and 0.69 g/cm3, will
the ball float or sink in a container
of gasoline?
Density
• The density of silver at 20 °C is
10.5 g/cm3. What is the volume
of a 68 g bar of silver?
Elements, compounds &
mixtures
Elements & Compounds
• Element – substance that
cannot be separated into
simpler substances by
chemical change, organized in
Periodic Table
Elements, compounds &
mixtures
Elements & Compounds
•
Element – substance that cannot be separated into simpler substances by chemical change, organized in Periodic
Table
• Compound – 2 or more
elements combined by
chemical change
Elements, compounds &
mixtures
Pure Substance or Mixture
• Pure Substance – has
unique set of chemical &
physical properties (includes
all elements and
compounds)
Elements, compounds &
mixtures
Pure Substance or Mixture
•
Pure Substance – has unique set of chem & phys properties (includes all elements and compounds)
• Mixture – blend of 2 or more
substances (not combined
chemically)
Elements, compounds &
mixtures
Pure Substance or Mixture
•
Pure Substance – has unique set of chem & phys properties (includes all elements and compounds)
• Mixture
Types:
•Heterogeneous – visibly
different parts
•Homogeneous – no visibly
different parts
– blend of 2 or more substances (not combined chemically)
Elements, compounds &
mixtures
Mixture Separation
•Filtration – often used for
heterogeneous mixes
Elements, compounds &
mixtures
Mixture Separation
•
Filtration – often used for heterogeneous mixes (not homogeneous)
•Distillation – heat liquid &
drive it off, leaving solid (or
liquid w/ higher boiling
point)
Elements, compounds &
mixtures
Mixture Separation
•
•
Filtration – often used for heterogeneous mixes
Distillation – heat liquid & drive it off, leaving solid (or liquid w/ higher boiling point)
•Crystallization –
evaporate liquid, leaving
solid
Elements, compounds &
mixtures
Mixture Separation
•
•
•
Filtration – often used for heterogeneous mixes
Distillation – heat liquid & drive it off, leaving solid (or liquid w/ higher boiling point)
Crystallization – evaporate liquid, leaving solid
•Chromatography – flow
solution along stationary
source