Question: Help! My mealworms have all died! Does anyone have any tips on keeping mealworms (alive) please? Answer: Purchase from the Bird & Fish Place in Welshpool Road Wattle Grove. Put them in unprocessed bran in a black bucket and feed them potato. The Perth Aquarium, 1234 Albany Hwy, Cannington ph 9351-8362 is also a…
Technical Tips
Manganese dioxide:
Question: How do you make the manganese dioxide pellets used for oxygen preparation please? The use of dilute hydrogen peroxide with the manganese dioxide powder produces a reaction thats often too vigorous and rapid. Answer: One part manganese dioxide to three parts plaster of Paris. Make a paste and leave it to dry over 2…
Limewater filtering:
Filter limewater through a coffee filter paper instead of decanting. It filters very well and is very quick. Use Harris brand unbleached natural paper size 102 but it probably doesn’t matter which brand. Normal lab filter paper clogs up and is very slow.
Lens cleaning:
Here is a tip for cleaning objective lenses on microscopes: Cotton buds are too big to reach inside the protective recess but toothpicks (the strong double-ended round ones) are ideal. Dip in alcohol or white spirit to dissolve the build-up and then the fine tip can be used gently like a brush. Finally, wrap one…
Laboratory Design Tips:
Have as much input as possible on design (both Science Technician and HOD) Keep checking floor plans as they are updated. Chemical resistant bench tops (very limited choice in colours). Chemical resistant, slip proof, strong durable vinyl floors. Stainless steel sinks with an outer lip are recommended. Island bench stations, with storage cupboards below. Lots…
Iodine Water Production:
Question: Have looked at the website and can’t find how to make iodine water. Can anyone help me please? Answer: 1. The recipe I have is from the Regional Technicians’ manual; it is as follows: Dissolve 12.7g of iodine crystals in 25mL ethanol and dilute to 200mL with distilled water. It is difficult to dissolve…
Indigo Carmine recipes:
1. 0.25g indigo carmine in 100mL of 50% ethanol. pH range 11.6 to 13.0 , colour change blue to yellow. 2. 1.0g per litre of 50% ethanol pH 11.6-14, blue to yellow.
Incubator alternatives:
Here are tips for growing cultures without an incubator or a warm place such as a hot water system. Use a 40w incandescent globe, still available from Kmart and Big W but not Bunnings. Place petri dishes side by side and cover them with black plastic (bin liner). To keep a check on the temperature,…
Hydrogen peroxide decomposition:
Question: Re experiment 36 in the STAWA Chemistry Laboratory Manual, Factors affecting the rate of decomposition of hydrogen peroxide, what it is in liver that is a catalyst for the decomposition? Answer: The enzyme which decomposes hydrogen peroxide in liver is catalase. The experiment works well.
Hydra culture:
Hydra is available from Southern Biological Services Pty Ltd, Victoria. Place Hydra in an 11cm petri dish or other glass or hard plastic container. Add about 2.5cm of Evian spring water. This seems to give the best results. It has been found that Hydra do not thrive in other types of spring water. Change the…