The following are recommendations for dishwashers in school science departments: 1. Probably most schools would have a domestic dishwasher. They work very well. We have a Whirlpool 6ADP 962, which features a half-load option and on the lower rack the plate holders can be laid flat to accommodate larger items. Test tube baskets are available […]
Digital cameras can be used take pictures of: Experiments – especially physics experiments, which you usually set up once a year. These, along with the experiment instructions, can be kept in a file. Field Trips – the terrain, clouds, orientation, experiments, finds, Science Technician snoring. Make these available to students who have missed the trip. […]
Try using plain label small freezer bags instead of cellulose tubing. It’s a lot quicker and a fraction of the price. Possibly most suitable for lower school.
For long periods of time, or when a vacuum is needed, use glass only. If it is only for overnight or not under vacuum, polycarbonate is suitable. They don’t have a good seal on them like glass desiccators so the silica gel needs checking regularly. They are unbreakable, can be easily washed and are very […]
Mix in roughly equal parts, the following: Petrol, diesel and used motor oil (ask a petrol station or service garage for their waste oil), or Turpentine, kerosene and clean motor oil (supermarket or hardware stock is fine) This should give a mix of boiling points from about 40 to about 300 degrees C. Crude oil […]
1. Reuse for the same prac only. 2. Soak in 3M or conc. HCl 3. Try dishwashing powder (has enzymes in it) 4. Throw away
Question: Does anyone know of a suitable water-plant for year 8s to be able to observe chloroplasts under the microscope? Answer: Use Valis (Vallisneria). Just pop it on a microscope slide, give it a little squash with your thumb and view. You don’t even need a cover slip and no stain. Just make sure you […]
Question: What is the best solvent to use in the extraction of pigments from chlorophyll? We have tried ethanol, acetone and a 50/50 solution of the two, but the bands aren’t great. Answer: You can use 1:1 ethanol: petroleum ether to extract the pigments then 2 percent ethanol : 98 percent petroleum ether to separate […]
Good epithelial cells result from scraping the smooth side of a lamb’s tongue with a moist toothpick, using the broad end of the toothpick. The cells are larger with more nuclei. Beef tongue can be used too but the results aren’t quite as good. You can show epithelial cells with nuclei from commercially prepared slides […]
Question: Is there anybody who knows about an alternative to the apparatus that is being used in Exp.12 STAWA Lab Manual: Charles Law? We have one, but it didn’t work the last time we used it. Answer: The apparatus should work fine, but it is necessary to tap the mercury bead before taking a reading […]