Breckland Scientific 2023 Catalogue

Gas

Gas Laws

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1 CHARLES’ LAW APPARATUS Apparatus used to demonstrate the thermal expansion of gases, to verify Charles law and to estimate a Celsius value for the absolute zero of temperature. Apparatus includes: Glass Charles law tube with graduated section, glass bulb, rubber stopper and clip; Tall glass beaker; Wire stirrer. Complete with instructions. Cat No. Description Price Per HPG-250-100 Charles Law Apparatus 44.72 ea. 2 CHARLES’ LAW MOUNTED Comprises a capillary tube, sealed at one end, with graduated scale from 0 to 200mm, mounted on a plastic former which also has a 0 – 70°C thermometer mounted alongside the tube. The glass tube includes a small bead of coloured oil, which has already been injected into the tube at about the 50mm mark, and the back plate has a hole at the top to allow fixing to a retort stand, so that the apparatus can be suspended in a tall beaker of water (not included). By heating the water and taking a temperature and scale reading every 30 seconds, a graph of the results can be plotted. Through a line of best fit and extrapolation absolute zero can be demonstrated. The straight line supports Charles’ Law, demonstrating that volume of a gas is directly proportional to its temperature, provided the pressure is kept constant. (In this case the pressure is atmospheric pressure). The Kelvin scale may then be introduced. 3 CHARLES’ LAW GRADUATED TUBE This simple Charles’ law tube consists of an unmounted capillary tube, sealed at one end, with a linear scale along its length, marked in cm and mm. Although traditionally used with a bead of mercury, a bead of concentrated sulphuric acid or coloured oil can be used instead, by inserting about half way down the tube, which can then be heated in a water bath to investigate temperature/volume for the enclosed air column. To place a bead of liquid into the capillary it is best to ensure the tube is thoroughly dried in an oven first, at high temperature, for an hour or two. After removing from the heat, if the tube is then immediately placed (briefly) with the open end in some coloured oil or sulphuric acid, a bead of liquid should be drawn into the tube as it cools down. Readings are taken directly from the scale on the tube. Comes supplied in a protective plastic case, with instructions. Dimensions: 300mm long x 7mm outer diameter, with scale marked from 0-27cm x 1mm. Cat No. Description Price Per HPG-275-100 Charles’ Law Graduated Tube 7.00 ea. 4 BOYLE’S LAW INDICATOR This simple low-cost apparatus provides a means of demonstrating Boyle’s law. It is not 100% accurate but it is adequate for demonstrations giving students literally a ‘feel’ for increase in pressure against volume. Cat No. Description Price Per HPG-150-100 Boyle’s Law Indicator 16.17 ea. 5 BOYLE’S LAW APPARATUS Apparatus for the recording of pressure versus volumes and for investigating Boyle’s Law. The vertical tube is part- filled with coloured liquid and sealed. The trapped air is then compressed progressively, with pressure (p) and volume (v) readings taken at each stage. Before each pair of readings is taken, the liquid should be allowed to settle so that the heat caused by the compression is dissipated. Please note: oil is no longer included as coloured water can be used instead. Bicycle pump not included. Cat No. Description Price Per HPG-100-100 Boyle’s Law Apparatus 179.78 ea. Dimensions: Glass tube, 245mm long; Overall length, 350mm. Available individually or as a class set of 10 in a Gratnells tray. Replacement capillary tubes with oil beads, sold as a pack of 10. Cat No. Description Price Per HPG-265-100 Charles’ Law Mounted 19.68 ea. HPG-265-110 Charles’ Law Mounted Class Set - NEW! 186.88 10pk HPG-265-200 Replacement Tubes with Oil Bead 63.00 10pk

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Charles Law Apparatus

Mounted Charles Law

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Charles Law Graduated Tube

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Boyle’s Law Indicator

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Boyle’s Law Apparatus

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