Storage of offal: Is it acceptable to store offal, such as plucks, hearts, kidneys, etc., in a freezer for long periods (months) for future use?

Storage of offal: Is it acceptable to store offal, such as plucks, hearts, kidneys, etc., in a freezer for long periods (months) for future use?
GHS Hazard category ratings: Can some one please explain the rating on the chemicals in the SDS please?
Lab dishwasher: We need to purchase a new dishwasher for the laboratory and are considering a domestic model with stainless steel interior ( I think they all have this now). Has anyone done this?
Sulfuric acid - going brown: Would you please tell me why concentrated sulfuric acid goes brown?
Endothermic reaction disposal of products: How can I dispose of the products of the reaction between Ammonium thiocyanate and barium hydroxide?
Thanks
Broken Max Min Thermometer: We have some max min mercury thermometers here, and yesterday one of them was broken by a cleaner. The broken thermometer gives off an overpowering odour, it was e
Recommended Chemicals for secondary Schools: I have to order new chemicals for our school in QLD, but the following chemicals are not in the list "List_of_recommended_chemicals-18March-2016.
Microscope servicing: Can any one recommend a microscope servicing company/person who would do the Gold Coast area please?
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,