Barium nitrate solutions: Is a 0.1M solution of barium nitrate permissible for years 7-10 in NSW Department of Education Schools? It is not clear in the CSIS chemical search.

Barium nitrate solutions: Is a 0.1M solution of barium nitrate permissible for years 7-10 in NSW Department of Education Schools? It is not clear in the CSIS chemical search.
Copper Sulfate Crystals: Is there a way to re-use copper (II) sulfate crystals to make another saturated solution?
Science ASSIST is sponsored by CSIRO Education.