138 1-800-452-1261
Colorimeters See pages 634–635.
Condensers, Liebig, Borosilicate Glass
Sealed-in condenser tube. Inlet and outlet on opposite sides of the jacket. Two jacket
lengths are available. Inlet opening diameter is 21 mm. Accepts 3/8" i.d. tubing.
Catalog No. Description Size Price/Each
GP1070 Condensers, Liebig, Borosilicate Glass 200 mm $ 93.00
GP1075 300 mm 114.00
Organic Chemistry Glassware See pages 325–326.
Condensers, Liebig, Borosilicate Glass
GP1070, etc.
Wash lab glassware as quickly as possible after use. If the glassware cannot be
washed immediately, then place it in the sink or a container to soak. Frequently,
this single step will loosen material that later becomes very stubborn.
Actual washing should be done with detergents like those in this section.
The water should be as hot as can be tolerated. Brushes should be used to
help remove stubborn deposits. Avoid using any worn brushes with metal that
can scratch the glass and accelerate breakage, rendering the vessel unsafe.
Glassware that is heated will break more easily from such a scratch than will
glass at room temperature.
Set Up a
Distillation Apparatus
Thermometer
Thermometer Connector
Round
Bottom
Flask Outlet
Water
Bath
Do not allow even weak acids to come in contact with a piece of glassware
before the detergent (or soap) is thoroughly removed. If this happens, a film of
grease may form on your glassware.
Grease is best removed in a weak (10% or less) solution of sodium carbonate.
Acetone may be used—but take all precautions.
Be sure all detergents, soaps and cleaners are rinsed from your glassware or
the residue will interfere with later chemical reactions. Rinse in tap water and
then dip-rinse in a container of distilled water.
Use draining racks to dry the glassware and reduce breakage.
Clean and Wash Glassware
• Do not distill to dryness.
• Use extreme caution when distilling mixtures containing flammable
liquids.
• Do not distill liquids with boiling points below 50 °C.
• Use only cold water in the condenser.
• Never leave a distillation unattended.
• Never heat or distill in a closed system.
Bulb
Hot
Plate
Cooling
Water Inlet
Three-way
Adapter
Condenser
Collection
Flask
Open to Air
Safety Note: Never heat or distill in a closed system!
Notice that the vacuum adapter is open to the air.
Conductivity Meters
Flinn Conductivity Meter
Testing the conductivity of solutions can give
important insights into the nature of, and the
particles in, a solution. This conductivity meter uses a green and a red light emitting
diode (LED) to quantitatively measure the conductivity of a solution. The green LED
requires more voltage than the red LED. Immersing the electrodes into a weakly
electrolytic solution results in a dim glowing of the red LED while the green LED
remains off. A strong electrolyte solution will cause both the red and green LEDs to
glow. The scale below, which is also affixed to the meter, can be used to measure and
compare the conductivity of various solutions. The meter is sufficiently sensitive that
it will display low conductivity for 70% alcohol solutions and medium conductivity
for tap water.
This conductivity meter is safe—no electric shock is possible because only a 9-volt
battery is used. And, because it is battery operated, the device is entirely portable.
The meter cannot easily be shorted out, particularly since an ON/OFF switch is
provided to disconnect the circuit even during storage. The electrodes are easily
interchanged or replaced.
See free video at flinnsci.com.
Scale Red LED Green LED Conductivity
0 Off Off Low or None
1 Dim Off Low
2 Medium Off Medium
3 Bright Dim High
4 Very Bright Medium Very High
Catalog No. Description Price/Each
AP1493 Flinn Conductivity Meter $24.70
Flinn Conductivity Meter
AP1493
Conductivity Tester
Simply plug this conductivity tester into a 110-Volt outlet and insert it into a series
of solutions to visually demonstrate to your students the relative conductivity of the
solutions. The lamp will shine brightly for strong electrolyte solutions, less brightly
for weak electrolyte solutions, and will not shine at all for non-conducting solutions.
The conductivity tester is safe to use with students because the electrodes are
completely surrounded by nonconducting material and the cord is positioned so
that it will not come into contact with the test solution. Requires a 15-watt lamp sold
separately. Includes background information and instructions.
Catalog No. Description Price/Each
AP5355 Conductivity Tester $48.45
AP5886 Lamp, 110-volt, 15-watt 8.80
CONDUCTIVITY METERS continued on next page.
Conductivity Tester
AP5355
CONDUCTIVITY
STUDY KITS SEE
PAGES 280–281
AND 297.
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