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LabEquipment

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COMMON LAB
EQUIPMENT USES AND VOCABULARY
REVIEW
Tools for Understanding Matter
Alabama Science in Motion
Updated Jan 2017
1
Which piece of lab equipment would be
the best to crush a solid into powder?
2
Which piece of lab equipment would be
the best to precisely deliver 5 mL of liquid?
3
COMMON LAB
EQUIPMENT AND USES
4
Beaker
Beakers are used
to mix chemicals,
dissolve solids into
solutions,
heat or cool
solutions and
measure liquid
volume in mL.
They have very
poor accuracy and
should only be
used to estimate
volumes.
5
Erlenmeyer Flask
Like beakers, Erlenmeyer
flasks can be used to mix,
dissolve solids into
solutions, and heat or cool
solutions. Unlike beakers,
Erlenmeyer flasks were
developed for swirling
solutions with minimum loss
and they can be plugged
with stoppers and used to
catch vapor or condensed
liquid. Their graduations
are not very accurate.
6
Graduated Cylinder
Graduated Cylinders
are used to more
accurately measure
volumes of liquids in
milliliters (mL).
Measurement readings
should be taken at eye
level from the bottom
of the meniscus, the
concave curved
surface formed at the
top of the liquid.
7
Volumetric Flask
A Volumetric Flask is
used to accurately
prepare solutions. A
weighed amount of solid
chemical is placed at
the bottom, and the
liquid solvent is added
until the fill line is
reached.
The volumetric flask
shown here is used to
prepare a 250-mL
solution at the fill line.
8
Pipet (Pipette)
Pipets are used to
measure or transfer
liquids.
Mohr pipets
(shown) are graduated
pipets used for
precise
measurement.
A pipet pump (top) or
a pipet bulb (bottom)
is attached to the end
of the pipet to help
draw up and release
liquid.
9
Micropipet (Micropipette)
A micropipet is a
precise method used
to transfer small
volumes of liquids in
chemical, biological
and medical
laboratories. Pressin
g on a plunger
button at the top of
the micropipet will
pull the liquid in,
and a second press
will dispense it. The
tips are disposable.
10
Dropper
A dropper is a
glass tube with
a hollow rubber
bulb at one end
and a small
opening at the
other, for
drawing in a
liquid and
expelling it in
drops.
11
Buret (Burette)
A Buret is an extremely
accurate device with a
stopcock at the bottom used
to measure volumes of
reagents.
Burets are often used to
determine the concentration
of a solution by dispensing a
solution with a known
concentration in a process
known as titration.
(Shown with Ring Stand and
Double Buret Clamp)
12
Ring Stand
A ring stand is a
metal stand consisti
ng of a long upright
rod attached to a
heavy rectangular
base that is used
with rings and
clamps for
supporting
laboratory
apparatus.
13
Double Buret Clamp
A double
buret clamp
is attached
to a ring
stand to
hold up to
two burets.
14
Support Ring
An iron support
ring is mounted
to a ring stand
and is used in
chemistry labs to
stabilize flasks,
beakers and
other glassware
and support them
over the work
area.
15
Test Tube Clamp
A test tube clamp
is attached to a
ring stand and is
used to hold test
tubes and other
cylindrical pieces
of equipment such
as burets, gas
collection tubes,
data-collection
probes, etc.
16
Test Tube Rack
Test tube racks
are used
for holding test
tubes upright
when they contain
chemicals, and
also hold test
tubes upside down
to dry.
They can be made
of wood, metal, or
plastic.
17
Test Tube
Test tubes are narrow
glass cylinders, closed at
one end, that are used
for mixing, heating, and
storing small quantities
of chemicals.
They are usually made
of a type of glass (such
as Pyrex®) that can
withstand high
temperatures.
Test tubes come in many
different sizes.
18
Test Tube Brush
A test tube
brush is used
for cleaning
test tubes and
narrow mouth
laboratory
glassware,
such as
beakers and
flasks.
19
Funnel
Funnels are used
to pour liquids
into narrowmouth containers
such as flasks and
bottles.
Buchner funnels
(pictured
right) are special
two-piece funnels
for filtering
mixtures through
filter paper into a
filtering flask.
20
Mortar and Pestle
A mortar and
pestle is a device
used since ancient
times to prepare
ingredients or
substances by
crushing and grinding
them into a fine
paste or powder.
The mortar is a bowl,
typically made of
hard wood, ceramic
or stone.
21
Crucible and Cover
A crucible is used
to heat solid
chemicals over a
burner at high
temperatures.
They are made
from heatresistant ceramics
to prevent
breakage.
A cover is used to
contain any smoke
particles.
22
Clay Triangle
A clay
triangle is
used to hold
a crucible
while it is
being
heated.
23
Watch Glass
Watch glasses
can be used to
cover beakers,
evaporate
water from
solutions,
weigh out solid
chemicals, or
observe
samples under
a stereo
microscope.
24
Evaporating Dish
An evaporating
dish is used to
separate water and
solids from a
solution by allowing
the water to
evaporate off into
the air. This is
usually done by
heating the
evaporating dish
over a burner or
hot plate.
25
Bunsen Burner
A Bunsen
burner is
attached to
a gas line
and lit to
provide heat
for
performing
experiments.
26
Hot Plate
Hot plates are
generally used
to heat
glassware or its
contents.
Some hot
plates also
contain a
magnetic stirrer,
allowing the
heated liquid to
be stirred
automatically.
27
Hot Mitt
A hot mitt
is used to
grip and
transfer hot
glassware.
28
Wire Gauze
A Wire gauze is a sheet
of thin metal that has
net-like crosses or
a wire mesh. The purpose
of wire gauze is to be
placed on the support
ring that is attached to
the ring stand between
the Bunsen burner and
the beakers to diffuse the
heat and to support the
beakers or other
glassware or flasks during
heating.
29
Test Tube Holder
A test tube
holder is
used
to hold and
transport
hot test
tubes.
30
Crucible Tongs
Crucible tongs
are used
to hold and
transport
hot crucibles.
31
Beaker Tongs
Beaker tongs
are used to hold
and transport
hot beakers.
They have a
plastic coating
which should be
kept away from
heat/flames.
32
Weigh Boat
A weigh
boat is an
open
container,
often
disposable,
used
for weighin
g samples.
33
Scoopula (Metal Scoop)
A
scoopula,
or metal
scoop, is
an
instrument
used to
transfer
solids from
one place
to another.
34
Top-Loading Balance
Electronic balances are used
to measure the mass of
substances accurately. The
balance is calibrated so that
the amount of resistance
placed on the balance pan
corresponds to a given mass
value (which is then
displayed on the LCD
readout).
Do not place chemicals directly on the
balance pan. Use a weigh boat.
Top-Loading balances can
usually mass substances to
the nearest gram, tenth of a
gram or hundredth of a 35
Analytical Balance
Analytical balances are
much more precise and
cost much more than toploading balances. They are
sensitive to vibrations (be
still and do not lean on the
lab bench) and to air flow
(close the glass doors).
Most of the analytical
balances provided by AL
Science in Motion can mass
substances to 4 decimal
places (0.0001g).
36
Well Plate
The well
plate is a
flat plate tha
t looks like a
tray with
multiple well
s that are
used as small
test tubes.
37
Forceps
Forceps (tweezers) are
a handheld, hinged
instrument used for
grasping and holding
objects.
Forceps are used when
fingers are too large to
grasp small objects or
when many objects
need to be held at one
time while the hands
are used to perform a
task.
38
Thermometer
A thermometer is
used to measure
temperature in
degrees Celsius or
Fahrenheit.
Most sold today are
filled with alcohol
instead of mercury.
39
Ruler
A metric ruler, also
called a rule or, especially
in the printing industry, a
line gauge, is a measuring
instrument used in
technical drawing,
geometry, engineering,
printing and construction
to rule straight lines and
calculate distances in
centimeters and inches.
40
Stirring Rod
Stirring rods
are used to stir
mixtures and
facilitate the
pouring of
liquids.
Stirring rods are
usually made of
glass.
41
Wash Bottle
A wash
bottle is
used
to store
and
dispense
distilled
or
deionized
water.
42
Goggles
Goggles are to be
worn to protect
your eyes when
handling chemicals
or glass.
Make sure that
there is a good seal
at the forehead to
prevent chemical
splashes from
running down into
your eyes.
43
Apron
An apron is
personal
protection
equipment
(PPE) worn to
protect
clothing from
chemical
spills.
44
VOCABULARY
45
MATTER
• Matter is anything that has mass and takes up space
(volume).
• Density is the amount of matter in a given volume.
• Density = Mass / Volume , units: g/mL or g/cm3
• Matter is either a mixture or it is a pure substance.
• Mixtures can be classified into two categories –
• Homogeneous mixtures (the same throughout;
solutions)
• Heterogeneous mixtures (different throughout).
• Pure substances can be classified into two categories –
• Elements (made of only one type of atom)
• Compounds (made of two or more elements
chemically combined)
46
PHYSICAL PROPERTIES OF MATTER
• Physical properties can be observed or measured
without changing the composition of matter.
• Physical properties are used to observe and describe
matter.
• Some physical properties depend on the amount of
the substance being used and some do not.
• Examples of Physical Properties
• appearance
• texture
• color
• odor
• melting & boiling points
• density
• solubility
• and many others.
47
CHEMICAL PROPERTIES OF MATTER
• Chemical properties are any of the properties of
matter that may only be observed and measured by
performing a chemical change or chemical reaction.
• Chemical properties cannot be determined by
touching or viewing a sample; the structure of the
sample must be altered for the chemical properties to
become apparent.
• Examples of Chemical Properties
• reactivity with other chemicals
• toxicity
• flammability
• chemical stability
• ability to rust
48
ACCURACY & PRECISION
• Accuracy is defined as coming close to a true or
desired value, like the center of a bullseye.
• Precision reflects how well a series of measurements
agree with each other, whether or not any of them
are close to the true value. For the values to also be
precise, they would need to be very close to each
other (whether or not they hit the mark).
• Precision can often be adjusted using calibration to
yield values that are both accurate and precise.
• Scientists often report percent error of a
measurement, which expresses how far a measured
value is from the true value.
Michael Betts, Getty Images
49
MEASUREMENT
• A ruler is used to measure
distance/length.
•1 m = 100 cm = 1000 mm
•1 km = 1000 m
•1 in = 2.54 cm
• A balance is used to measure mass in grams.
Steps for using an electronic balance:
1.Place a weigh boat on the pan (close all doors if analytical
balance)
2.Press the zero/tare button & wait until digital units are
displayed
3.Place the object to be massed in the weigh boat (close all
doors
if analytical balance) & wait until digital units are displayed
1.Record the mass using all decimal place values shown (do not
50
MORE EQUIPMENT
(not as common in some high school
chemistry labs)
51
Three-Prong Clamp
A three-prong
clamp is attached
to a ring stand
and is used to
secure lab
equipment.
52
Graduated Pipet
A graduated
pipet is made
of disposable
plastic with
graduated
marking on it
so that a
precise
volume of
liquid can be
transferred.
53
Thin Stem Pipet
A thin stem
pipet is made
of disposable
plastic and is
used for
transferring
small amounts
of liquid,
usually one
drop at a
time.
54
Stopwatch
A stopwatch is a
watch that can be
started and
stopped for exact
timing.
It is used in the
science lab to time
how long
something takes to
complete such as a
chemical reaction
or the motion of a
moving object.
55
Centrifuge
A centrifuge is a
machine with a
rapidly rotating
container that
applies centrifugal
force to its
contents, typically
to separate fluids
of different
densities or liquids
from solids.
56
Petri Dish
Petri dishes
are used to
hold
specimens for
observation
and to grow
cultures.
57
Triangular File
A triangular
file is used in
the chemistry
lab to score
glass tubing
to create
clean
breaks in the
glass.
58
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