laboratory apparatuses and safety
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Lab Equipment
Pre-AP Chemistry
Charles Page High School
Stephen L. Cotton
Lab
Equipment
Your lab equipment should:
1. Be CLEAN before using it.
2. Be CHECKED (if glassware) for cracks, brokenedges, and stars discard anything damaged.
3. Be washed, dried, and carefully stored in theproper place after using it.
Cleaning Supplies
1. Each lab station has plenty of paper towels,soap, water, sponge and a sink. (2 sinks arealso located on the east wall desktop)
2. Used for cleaning lab equipment, the tabletop, and to wash your handswhen finished.
3. We have floor brooms, table brushes, anddustpans to clean up any spills.
Keep our lab area neatand clean!
Use this Broken Glassbox to dispose of anybroken glass, instead
of the trash can.
BeakersBeakers hold and/orheat solids or liquidsthat will not releasegases when reacted,or are unlikely tosplatter if stirred.
Very pooritem tomeasure volume with(+/- 5% error!)
Note the total sizecapacity = 250 mL(upper mark is 200 mL)
There are six sizes of beakers inyour lab table for you to use:
50, 100, 150, 250, 400, & 600 mL
Beaker Tongs Beaker tongsare used to hold
and movebeakerscontaining hot
liquids.
Note the rubbercoating toimprove grip onthe glass beaker- do not hold thesein a burner flame.
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Erlenmeyer Flasks
Erlenmeyer flasks
hold and/or heatsolids or liquidsthat may releasegases during areaction, or that are
likely to splatter ifstirred.
Note the size = 125 mL
Florence Flasks
Rarely used in firstyear chemistry, itis used for the
mixing ofchemicals. The
narrow neckprevents splash
exposure. Also called round-bottom flasks
Flask Tongs
Flask tongs are used only to handleflasks use beaker tongs for beakers.
Graduated CylindersA graduated cylinderis used to measurevolumes of liquids;probably your besteveryday measuringtool, there are threesizes in your desk:10, 50 and 100 mL
*NOT to be usedfor heating or
mixing chemicals
Note the rubberbumpers.
Some graduated cylinders that aresmaller may not have bumpers, but
have reinforced glass rims.
The top
plastic
bumper
ALWAYS
stays atthe top, to
prevent
breakage if
it falls
over.
Test Tubes we commonly use 2 sizes:
18 x 150 mm
13 x 100 mm
Largertube
(25 x 200 mm)
sometimesused
Test tubes are used to mix chemicals,and also used to heat chemicals in.
The size is determined by the diameter across the top andthe length of the test tube. Example: 13 mm x 100 mm
(diameter) (length)
Test Tube Holder
A test tubeholder is useful
for holding a testtube which is too
hot to handlewith your hands.
Knowing where
to hold this pieceof equipment is
important.
Holding it here will keep your hand as far aspossible from the fire, and prevent you from
squeezing the holder and dropping the tube.
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Test Tube BrushesTest tube brushes
are used to cleantest tubes and
graduated
cylinders.
Caution: Forcing alarge brush into asmall test tube willoften break the tube.Dont worry aboutdrying the inside of atube or cylinder - Letthem air dry instead of forcing a
paper towel down inside.
Small test tube brush
Large test tube brush
Test Tube Racks
Test tube racks are for holding, drying, and
organizing test tubes in a vertical position,and are located in the side wall cabinets.
Test tubes can be placedupside down on these
pegs for drying.
Stoppers
Rubber and corkstoppers are usedto close test tubes
and flasks, thusavoiding spillageor contamination.
Containers should NEVER be heated when
there is a stopper in place pressure willbuild up, and an explosion could occur.
Spot PlatesSpot plates are usedwhen we want toperform manysmall-scalereactions at onetime.
We will use thesemany times during
the year, and is likehaving lots of test
tubesavailable atone time! Numerous well depressions
Watch GlassA watch glass isused to hold asmall amount of
solid, such as the
product of areaction.
Can also be used
as a cover for anevaporating dish
or beaker.Since they may not be made ofheat-resistant glass, they are
usually not heated they break!
Stirring Rod with
rubber policeman
The stirring rod will:
a) manually stirsolutions;
b) assist in
pouring liquids; andc) transfer a
single drop of asolution to test
papers (like litmus)
Rubber policemantip is used to removeprecipitates.Stir with this end.
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Litmus Paper Red litmuspaper is used toidentify bases:
-Red turns blue,-Blue stays blue
Blue litmuspaper is used toidentify acids:
-Blue turns red,-Red stays red
Use a stirring rod to transfer asingle drop of liquid to the paper;dont drop the paper in the tube
Dropper PipetThe dropperpipet is used totransfer a smallvolume of liquid,
usually one dropat a time you
have both shortand long pipets.
On top of each dropper is a rubber bulbfor suction never put your mouth on thedropper to provide suction.
Graduated Pipet
A graduatedpipet measuresand deliversexact volumes
of liquids.
These will alsouse a rubberbulb for
suction.Many different sizes of graduated pipetsare available. Example: 10 mL or 25 mL
Graduations in mL
Forceps
Forceps are used to hold or pick upsmall objects Remember: it is bestto never touch chemicalswith your
hands.
FunnelA funnel is
used to:1) aid in
the transfer ofliquids fromone vessel toanother, and
2) holdfilter paper
while filtering.
(Some pieces of equipment are plastic, others are glass.)
Wash Bottle A wash bottle hasa tip that delivers astream of water toa specific area
when squeezed.
Distilled water isthe only liquid that
should be used ina wash bottle.Refill from the
gallon jugs on theeast desktop.
During use, keep the bottleupright as shown, since there isa tube that goes to the bottom
of the bottle.
H2ODistilledWateronly
To prevent contamination,dont touch the tip to otheritems, such as test tubes.
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Weighing Boat -
Weighing boats are used for holding anddetermining the mass of solid chemicals.
Never put chemicals directly on the balancescale they will leave a contaminating residue.
We will also use paper squares for this purpose we can throw the papers away after using.
A small plastic dish Electronic BalanceLocated on Table 8
(try to use the same scale during anexperiment for consistency)
The electronic
balances are veryaccurate, highly
dependable, andrugged.
The digital displaymakes the massvalue very easy toread.
On button Off button Tare button
Place item here to mass
42.57
Scoopula
Scoopulas are used todispense solid chemicalsfrom their containers.
The chemicalsshould never betransferred with
your bare hands.(assume they are all dangerous)
Spatulas aresometimes also used.
Burner Burners are usedfor the heating ofnonflammableliquids and solids.
We have Tirrellburners to use in
our classroom.
Hot plates will beused to gently heat
any flammablechemicals.
In order to get the best flame,you might need to make
adjustments each timeyou usethe burner practice this!
Lighter
Striker-style flint
lighters are usedto light your lab
burners.
The flints onstrikers areexpensive; do notoperate the strikerrepeatedly just to
see the sparks!
Squeezing the flint against thefile causes a spark, thus
lighting the burner.
Spark occurs here.
Evaporating Dish
The evaporating
dish is used forheating stable
solid compoundsand elements, aswell as for
evaporatingsolutions.
These are made of a porcelain material, and thereforecan withstand high heat temperatures, but are thin and
fragile, and break easily handle with care.
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Crucible and coverCrucibles are used
for heating certain
solids, particularlymetals, to veryhigh temperatures.The cover can beused to contain
any smokeparticles.
The crucible and cover are also made of a porcelainmaterial, and thus can withstand high temperatures.
Crucible Tongs
For handling hotcrucibles and their
covers; also used topick up other small
hot objects - NOT tobe used for pickingup beakers!
Clay Triangle
The clay triangle isused as a support
for crucibles whenbeing heated over
a lab burner.
It can also be usedto support a funnel
when filtering.
Triangular File
Triangular files are used primarily to cut
glass tubing, a skill that your instructor
will share with you later.
Ring stands and their Components
Ring stands are a safeand convenient way tosupport equipmentholding reactions thatrequire heating using alab burner.
The base can also be
used as an insulatingpad to place hot
objects on while theycool.
(Ring stands and their Components)
The Ring Clamp
Ring clamps connect
to a ring stand, andwhen used with a
wire gauze provide astable, elevated
platform for a beakerto rest when heated.
Will hold a clay triangle and funnel during filtering,and will be used with a clay triangle to hold a
crucible when they are heated.
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(Ring stands and their Components)
Wire Gauze
Wire gauze sits onthe ring clamp toprovide a platform to
stand a beaker.
On older wire gauze,the white materialwas asbestos
currently it is aceramic.
(Ring stands and their Components)
Test tube Clamps
Test tube clampsare used to securetest tubes, burets,and distillationcondensers to the
ringstand.
Many test tube clamps have a rubbercoating on the jaws to improve their grip.
Pneumatic Trough
When filled with waterand used with collectionbottles, they can be used
to capture gases that areproduced in reactions.
Note the overfilltube that drainsinto the sink
Ruler
We always use the Metric System(also called the International System)
to make our measurements.
Record your numbers as decimals,not as fractions.
Examples: 3.5 mm or 6.2 cm
Goggles and Goggle Sterilizer Cabinet Inside the Goggle Sterilizer Cabinet
Goggleswill besterilizedbefore
each classperiod toprotectyou ituses anultravioletlightsource.
Timer normally setfor 10 minutes.
Any volunteers todo this at the end
of a lab period?
Place goggles face side up, and neatly.
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Goggles and Aprons
GoggleAdjusting Straps
Goggle Venting Areas-do not remove these!
Be sure to securely tie your apron behindyour back, using the tie cords.
Eyewash StationPush this handle to
turn on the water itwill stay on until you
pull it to turn off.
It is possible to flush oneeye, or both eyes at the
same time. This should bedone for 15-20 minutes!
The Eyewash Station islocated in the back of
the lab, next to theSafety Cabinet and
under the SafetyShower. You will needto provide assistance toyour lab partner if they
need to go to theEyewash Station.
NOTIFY the Instructorimmediately!
Safety Shower
LOTS of waterwill come
pouring outhere to rinseoff chemicals
spilled on you.
NOTIFY theInstructor
immediately!This is the handle to
pull down toactivate the safety
shower it will staypulled down until it
is pushed back upto turn it off
Safety Cabinet and Contents
Items inside the Safety CabinetNeutralizer for
base spills
Absorbent forchemical spills
Mercury Cleanup Kit,and protective glovesFire Blanket
First Aid Kit
Fire Extinguisher(Class A,B,C fires) Neutralizer foracid spills(and more
extra gloves)Sand to
surroundand
containchemical
spills
Met-L-XMetals Fire
Extinguisher(Class D fires)
Fume Hood and Flammable Cabinet
Another fire extinguisher, inaddition to the one locatedin the Safety Cabinet at the
back of the room, and theone out in the hallway.(There are 3 total available)
The fume hood is an exhaust fanfor smelly or dangerous fumes.
Flammable chemicalsare stored in theselocked cabinets.
Note this location of the naturalgas master shut-off valve.
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Side Cabinet Storage located in thefour cornersof the lab
Use the cabinet closest to your labstation, and put only these items in
the cabinet.
Side Cabinets are for Ringstands, DistilledWater Bottles, and Test Tube Racks
4 Ring stands
4 Distilled water wash bottles
4 test tube racks
All items neatly stored when you are finished!
** On lab experiment days **
Bring REAL SHOES, REAL BRAINS, and your
LABORATORY MANUAL. Your calculator,textbook, and class notes are also suggested.
The Chemical Storeroom
Students are notallowed in the
storeroom wherechemicals and
glassware arekept.
Materials youneed will beavailable to youin the lab area.
To clean up spills and/orbroken items, use the:
Table brushes anddustpan
Floor broomsfor larger spills
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