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Upon searching through an old storage room, you come upon the equipment that was used to study this reaction the last time the company investigated it, nearly twenty years ago. Looking at the equipment you think to yourself "I haven’t seen such a minimal experimental apparatus since my undergraduate days at U.B. Oh, well, given the short deadlines, I guess I don’t have any other options except to use this. I never realized at the time how valuable my U.B. lab experience would prove to be!" The equipment consists of two variable speed pumps, an electrical conductivity probe and readout:
a constant temperature bath with a recirculator:
a reactor with a motorized stirrer and cooling coil:
a couple of thermometers, some beakers and some tubing. You drag it back to the lab, and comparing what’s available to the old company reports on the subject you are able to reconstruct the equipment. Figure 1 is a photograph of the apparatus after you have gotten it put back together, including the probe modification you decided upon previously. Here is a schematic diagram of it.
Having the equipment back together, you go to the company library, and together with the librarian you are able to locate the manuals for each of the key components of the apparatus. The pumps are simple to operate. They each have an on/off switch, a forward/reverse switch and a rotary dial/readout. The rotary dial is used to set the flow rate, so you had your technician make a calibration curve giving the flow rate versus the dial setting for each of the pumps. The technician has plotted the resulting calibrations and posted them near the apparatus. The temperature bath/recirculator is equally easy to use. It gets filled with a heat transfer fluid, which for this experiment can just be water. A beaker full of distilled water (to be used as a reactant) is placed inside the bath via the opening in its top. The level of the distilled water inside the beaker is below the level of the heat transfer fluid outside the beaker. In this way the distilled water is preheated to the desired temperature. A separate set of tubes carry heat transfer fluid out of the back of the bath/recirculator, through a small copper heating coil that is immersed in the reactor (just another beaker), and back again to the bath/recirculator. A single switch turns the bath recirculator on, and a dial is used to adjust the temperature. |
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last update: 02/11/99
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