Bullet Head nails from Bunnings work well 3, 4 or 5mm diameter mild steel round bar from a steel supplier. This is a softer iron alloy, so it will rust more readily. Very cheap. Black rod ties, for rebar Zinc plated, non-galvanised nails from Bunnings rust the best.
Technical Tips
Casein Powder Substitutes
Our students test dilute casein solution with Benedict’s reagent, Biuret test etc as part of a ‘carbohydrates and proteins in foods’ prac. Food Sample recipes from STAWA Human Biology Laboratory Manual exercise 19 (undated): Sample A = laundry starch or starch powder + gelatin powder + washed white sand. Sample B = glucose powder +…
Making Lime Water
Add 2-3 spatulas of calcium hydroxide into a 500ml stock bottle and make up with distilled water. Give it a really good mix, then allow the solids to settle. You can filter off the solids if you prefer. Limewater is saturated calcium hydroxide Ca(OH)2. Add the (solid) calcium hydroxide to water until no more will…
Drying Glassware Quickly
Rinse with ethanol, methylated spirits or acetone in a well ventilated area. Works faster if glassware is hot. Use a hairdryer or incubator. Acetone or blow with N2 gas (if available) If volumetric flasks are rinsed with distilled water, they don’t need to be completely dry when making up chemicals. Place them in an oven –…
Pollen Jelly Recipe
https://www.bing.com/ck/a?!&&p=f69818eda6aa5940JmltdHM9MTY3NjQxOTIwMCZpZ3VpZD0wMjcxOTQwYS1iOTVkLTY3ZWMtMjFlOS04NWJiYjhjZDY2NjUmaW5zaWQ9NTIwMg&ptn=3&hsh=3&fclid=0271940a-b95d-67ec-21e9-85bbb8cd6665&psq=pollen+in+jelly+science+prac&u=a1aHR0cHM6Ly93d3cubWljcm9zY29wZW1hc3Rlci5jb20vcG9sbGVuLXVuZGVyLXRoZS1taWNyb3Njb3BlLmh0bWw&ntb=1
Safe Handling and Storage of Radioactive Equipment
Perth Scientific and Haines supply a small cylinder that is suitable for storing small radioactive sources. For larger radioactive sources, members reported buying a lead sheet from Bunnings which was used to line a steel toolbox. As an added precaution the radioactive sources can be Radiation gloves are not required for the low level…
Effect of Temperature and pH on 2 Enzymes: Amylase and Pepsin
pH Each enzyme has an optimum pH, above or below which their activity is lower. Supply students with 5 ph buffers i.e ph 2,4,7,10 and 12 Activity was measured by transmittance and absorbance using a Mystrica colourimeter Temperature: All reactions are faster at a higher temperature, however the enzyme-catalyzed reactions become slower or stop if the temperature is too…
Tips on what to use as a secondary container in an Autoclave
Roasting Bags Biohazard bags placed into the secondary container provided with the autoclave A glass beaker
Removing a rubber stopper stuck in a glass flask.
Possible Causes: 1.Rubber stopper fitted tightly in the flask. Flask neck might be slightly narrow for the stopper or the stopper is slightly too small for the flask. 2.Rubber stopper has hardened somewhat with age to the point where rubber attains a strong bond with glass. 3.Rubber stopper is stuck due to vacuum formed inside…
Making Hand Sanitizer
Ingredients 250mls of 91% isopropyl alcohol 125mls of aloe vera gel (natural or store-bought) 15 drops of tea tree oil (or another antibacterial essential oil) 1. Pour the alcohol into a medium beaker. 2. Measure and pour the aloe vera gel. Alcohol can be hard on your skin, so using aloe is a good way to counteract that effect and keep…