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TGHS4: Practical notes: use of gas bags LINKS Page Name of Video Clip Notes N2.1 Sulfur freezing This is demonstrated safely because the heating is very slow, hence no sulfur vapour escapes and ignites. Done less carefully, there is some chance of the sulfur igniting and forming toxic sulfur dioxide. It is advisable to put a plug of mineral wool in the mouth of the tube, and to remove it before pouring. N2.2 Lead crystals The lead was reacted with 2M nitric acid (corrosive). O2.3 Distillation Liebig In a school laboratory, the Liebig condenser should be clamped or supported (this was omitted in the video for reasons of visibility) P2.5 Magnesium and oxygen A number of video clips refer to 'oxygen', when describing activities involving a reaction with air (i.e dilute oxygen). This video clip really does show the use of pure oxygen, and thus the reaction will be more vigorous and the flame will be much brighter. Uses 'gas bag' - see note To return to the page of main content the note refers to, click on the page number in the table. main content n2.1 main content n2.2 main content o2.3 main content p2.5 more info tghs1: health safety tghs2: notes tghs3: notes tghs4: notes tghs5: notes tghs6: notes more info   < prev | next >

a Science Enhancement Programme CD-ROM 2005   user guide