General Catalogue Chemistry - BECO Internacional LTDA.

Classroom experiments
with superconductors
Equipment list
For determining the transistion temperature
electrochemistry
Turbulent developments in the field of ceramic
superconductors have followed in the wake of
the Nobel Prize being awarded to J. G. Bednorz
and K. A. Müller in 1987. The superconductor
effect was discovered in 1908 by Kamerlingh
Onnes while he was conducting systematic
examinations of the conductivity of metals at
low temperatures. He determined that mercury
loses its electrical resistance entirely once it is
cooled to below the critical temperature –
sometimes called the transition temperature.
In the case of mercury this temperature is at
4.2 Kelvin or –269.0 °C. This means that all the
experiments required cooling with liquid helium.
With the aid of ceramic superconductors it
has in the meantime become possible to raise the
transition temperature to above 100 K, which
has alleviated many ot the difficulties otherwise
encountered in expermental and industrial uses.
One of the amazing things about the development
of the recent years is the speed at which
breakthrough experiments have been duplicated
among lay persons. Just a few months after the
publication of the scientific reports there were
»recipes« in a variety of magazines, describing
the production of the superconductors with
simple technical facilities.
Quantity Description Cat. No.
1 Experiment kit for determining the
transition temperature and electrical resistance . . . . . . . . . . 667 552
2 Multimeter METRAMax 2* . . . . . . . . . . . . . . . . . . . . . . . . . . 531 100
alternatively
1 Senor-CASSY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 524 010
1 CASSY Lab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 524 200
Determination of the transition temperature with the computer
LEYBOLD DIDACTIC · GENERAL CATALOGUE CHEMISTRY
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