WARNING! This experiment is dangerous! You should NOT perform this at home. ONLY carry out this experiment, if you are a trained chemist, and you understand local safety and legal requirements, which are required to perform such experiments
- The first synthesized substance in this experiment is cobalt (II) arsenate. Prepare about 50 ml of cobalt nitrite (pink) solution and sodium arsenate (colorless) solution.
- Mix them in a beaker. The formation of purple precipitate is observed.
- The second pigment is paris green – green colored cooper (II) acetarsenite. For this experiment we need arsenious oxide, sodium carbonate solution, copper sulfate solution and acetic acid solution.
- To obtain cooper (II) acetarsenite first we need to get sodium arsenite solution. For this purpose add some arsenious oxide to sodium carbonate solution (about 20 ml). A little heating may be required for better dissolving.
- Then take copper sulfate solution and mix it with acetic acid solution. Put it on a magnetic stirrer. 6.Slowly pour the sodium arsenite solution to the mixture of copper sulfate and acetic acid solution. On this stage you should avoid the formation of precipitate and mix the components very carefully. A bright blue clear solution will be obtained.
- Heat this solution to boiling for a few minutes.
- The mixture turns green and solidifies because of the cooper (II) acetarsenite formation.
- The last synthesized substance in this experiment is arsenise sulfide - orpiment. Prepare about 50 ml of mixed sodium arsenate and acetic acid solution and about 25 ml of thiosulfate solution.
- Put an empty beaker on a magnetic stirrer.
- Pour both solutions in the beaker. Wait for a little.
- A yellow precipitate is formed.
- To isolate synthesized pigments the suspensions should be filtered and precipitates should be left to dry.