School Science/Making Charles' law tubes Charles' law tubes
allow the demonstration of Charles' law in a school lab. Heat
the tube in boiling water, drying oven or with a hot air gun and
place open end in clean mercury. Allow tube and the air in it to
cool, drawing a thread of mercury about 5mm long up into the
tube. Allow all to cool to room temperature. To move the thread
of mercury further down the tube, to ensure it is not expelled
when the tube is heated to 100°C during the experiment, pass a
short length of nylon fishing line (approx 0.5mm diameter) down
the tube and through the mercury. This allows the air below the
mercury to leak out around the line and when the mercury has
fallen to the required position, remove the nylon line. This
should ONLY be done if one has proper safety training regarding
the hazards of mercury and the school is equipped with proper
mercury spill kits for containing and cleaning any potential
spills.Last modified on 22 March 2010, at 04:30