Chemistry

From CSBLwiki

cleaning solution

• from Safety Manual
  • Preparation of Dichromate Cleaning Solution. It is occasionally necessary to use a strong oxidizing agent such as a mixture of a dichromate salt (sodium or potassium) and sulfuric acid for cleaning stubborn residual deposits on glassware. This chromic acid mixture may be stored and reused until it becomes green in color.
  • To prepare such a solution, one places approximately 10 g of sodium dichromate in a 2-liter beaker and adds just enough water to dissolve the salt completely. While the potassium salt may be used, the sodium one is preferred since it has greater water solubility. Then approximately one liter of concentrated sulfuric acid is added very slowly and gradually to the water solution to avoid splattering. The solution is most effective when hot. The solution may be stored in 1-liter, glass stoppered bottles
  • another source (PDF)
  • 공주대 분석화학실험실