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TGHS2: Practical notes topics A-G LINKS Page Name of Video Clip Notes A1.1 Wax melting in tube The video shows a sample of wax that had previously been boiled for 5 minutes. Without this, many small bubbles appeared when in close-up view as the wax melted. (This occurred for a variety of sources of wax, including reagent grade stearic acid). A3.2 Salt melting in tube It is easier to melt a given amount of salt in large lumps rather than small grains. C1.2 Water into syringe The syring is hot (150 C). Take care not to touch it if putting a finger behind it to show the transparency of the gas. Also, keep careful control of the syringe needle. C3.3 Boiling point Wax vapour is highly flammable. To avoid this igniting, it is important that the tube is long relative to the amount of wax, as shown in the video. G5.1 Evaporating water and propanone Propanone is highly flammable. There must be no naked flames nearby. To return to the page of main content the note refers to, click on the page number in the table. main content a1.1 main content a3.2 main content c1.2 main content c3.3 main content g5.1 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