Calcium Carbide: My teachers are wondering whether there are any restrictions on us storing and using Calcium carbide for pracs here at school?
Mitosis in onion root tip: Are there alternative stains for mitosis in root tips please? It needs to be inexpensive (I've been quoted $150 for 5 gm orcein, including postage), not too hazardous,
Employment: Are there any standards or recommendations regarding the number of hours a lab technician should be employed?
Safe concentration of HCl for Year 8 students to use?: A year 8 textbook has an activity which includes an example for a colour change (blue litmus paper with HCl added to it).
Balloons: I haven't heard of any issues but we have a parent who is concerned with regards to balloons and latex and the powder residue in them.
Third party Safety Data Sheets (SDSs): Can you clarify the requirement for a manufacturer's SDSs versus a third party SDSs?
Copper Sulfate Crystals: Is there a way to re-use copper (II) sulfate crystals to make another saturated solution?
Autoclaving disposable Petri dishes: How do you use a biohazard bag and can plastic disposable Petri dishes be autoclaved in them?
SDS for non-hazardous chemicals: Do my suppliers need to supply me with a SDS for a non hazardous chemical if I ask for it?
Labelling of solutions: This may have been asked before but do diluted solutions of chemicals need to be labeled with the new GHS and if so, do the ones that I have now have to be re-labeled or is