 The Graduated Cylinder
• Volume
 The Thermometer
• Temperature
 The
Electronic Balance
• Mass
 Handling
Solids/Transferring Solids to a Test
Tube
 Decanting and Filtering a Solid
 The Laboratory Burner
 Liquids
in graduated
Cylinders
 How precisely you can
measure volume
depends on the size and
type of graduated
cylinder you use.
 You should be able to
estimate between the
marked
lines…graduations.
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It is important to notice what each line or
interval on the graduated cylinder
represents.
Different kinds of graduated cylinders are
set up differently.
A 10 milliliter cylinder, for example, usually
has one tenth of a milliliter for each
graduation
Some have two-tenths milliliter for each
graduation.
The way to check this is to count the
divisions between consecutive numbers.
Estimate your measurements by reading
between the lines, you should be able
to read one digit past the marked
scale.
numbers are 10, 20, 30,
etc., so there is a 10
milliliter increment
between them.
 Since there are 10
divisions between
consecutive numbers,
each division represents
one milliliter.
 Therefore, you should be
able to estimate to tenths
of a milliliter by reading
between the lines.

 On
your 50 mL cylinder
each mark is one mL
 So read to the tenths
place
 Just like on the 100 mL
cylinder
 Marked
to the 10ths
 Estimate to the 100ths
 Measurement has 2
places past the decimal
 liquids
pull up the sides
of a glass container
 This curvature is called
the meniscus.
 Concave meniscus
 Read the center bottom
of the meniscus.
 In
some plastic cylinders
water has a flat surface.
 In that case top or
bottom doesn't matter,
but we can still say use
the center rather than
the edges.
 some
materials where
the curve goes the other
way.
 A Convex Meniscus
 Read the top center of
the meniscus.
 Increase
the visibility of
the visibility of the
meniscus by placing a
paper or your hand
behind it.
1.
2.
3.
4.
5.
6.
Add some water to your
100 ml graduated cylinder.
Read the volume of the
water. Record in your lab
notebook.
Add some water to you 50
mL cylinder.
Record the volume in your
lab notebook.
Repeat with your 10 mL
cylinder.
Add all the water to a
clean beaker.
 Measures
Temperature
 Use the Celsius Scale
 Degree is the Unit
 Based on freezing and boiling point of water
 0 degrees C
 100 degrees C
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
do not have to be shaken
down.
hold a thermometer while
using it. The container it is in
may or may not be able to
support it.
All you have to do is put the
thermometer in the liquid
and watch the alcohol level
change.
When it stops changing,
read the alcohol level.
This is your measurement.


Estimate between the lines.
Mentally divide the
graduations (marks) into 10
equal parts in order to read
to a tenth of a degree.
PARTIAL IMMERSION
THERMOMETERS ARE DESIGNED
TO INDICATE THE ACTUAL
TEMPERATURE WHEN A
PORTION OF ITS STEM IS
EXPOSED TO THE TEMPERATURE
BEING MEASURED.
Immersion Line must be below
the water level
1.
Measure the
temperature of the
water.

Make sure it’s turned on and registering zero. If not hit zero/tare to zero
the balance.



Do not place chemicals directly on the balance pan
Do not place hot materials on the balance
Do not place anything too heavy on the balance (200 grams max)

Always weigh the chemicals in or on something
• a weighing dish, a beaker, or a piece of folded paper.


Remember to weigh the container first
or adjust (tare or zero) for its mass.

Be careful not to spill any chemicals on or around the balance. If you do,
clean up immediately!

If for some reason your balance doesn't seem to be adjusted properly, let
the instructor know. Don't just try to fix it yourself.
1.
2.
3.
Mass about 10 grams of NaCl (table salt)
using the electronic balance.
Add the solid to the beaker of water and Stir.
Record your observations.
Add one teaspoon of sand to the salt and
water mixture. Stir. Record your
observations.
 Decant:
pour off any excess water after
allowing the solid to settle
 Filter the sand from the salt water mixture as
directed by the teacher.
 Weigh
solid onto a piece of paper or weigh
boat
 Push edges of paper or boat together so that
they form a trough
 Slide solid into the test tube
 Remove
stopper with back of hand.
 Hold stopper in hand while picking up the
bottle and pouring the liquid down a stirring
rod to prevent splashing.
 Do not put the stopper down.
 Gas
Jet
 Barrel
 Base…stays
cool
 Gas Adjustment knob
 Air Adjustment
 Clear
the area of any flammable materials
 Close the gas adjustment completely then open 3-4
turns
 Adjust air if necessary
 Have striker ready
 Turn gas on at gas jet
 Light burner
 If you do not get it lit in 2 strikes… turn gas off and
start over.
1.
2.
Light the burner as
demonstrated.
Extinguish the burner.
Repeat. Make sure
each partner can do it
efficiently.
Set up a ring stand,
burner, and wire gauze
as demonstrated.
Make 25 mL of salt water.
 Set the beaker of
saltwater onto the wire
gauze.
 Light the burner and put it
under the wire gauze.
 Evaporate the water from
the salt.
 Observe the crystals left
behind. Use a hand lens.
What do you notice about
the crystals?

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
Don’t look directly into a test
tube being heated.
Don’t point it at yourself or
others.
Move it back and forth through
the flame to control the
heating.
Be careful that it does not boil
out.
It will heat much faster than
you expect.
 How
good are your lab skills?
 Illustrates
the importance of carefully following
lab procedure and making careful measurements
in order to achieve reproducible results.
 You have 20 minutes. Including answering lab
questions.
 Work quickly, but carefully.
 You will be able to assess your skills at the end of
this activity.