Gold is a precious soft metal of yellow color. The nobility of this metal is estimated by the fact that it is resistant to influence of hostile environment, i.e. is not oxidized under the influence of acids and alkalis. It is possible to emit gold from gold-bearing materials in two ways mechanical (manually) and chemical.
It is required to you
- Nitric, sulfuric, hydrochloric acid, glass capacity, magnet.
Instruction
1. Remove gilding from metal products. Take any gilded product and place it in glass capacity. Then, accurately pour in capacity nitric acid (pour acid in the portions) so that it completely covered a product. Reaction with dissolution of metal which is covered with gold will begin.
2. After the end of reaction when metal is dissolved, at the bottom there will be a gold which covered metal. Merge solution having separated it from a deposit. Wash gold with water.
3. Emit gold from gold-bearing sand. Scatter gold-bearing sand on a table and carry out on it by a magnet. At the same time all ferromagnetic materials will be attracted to it.
4. Further, process sand of the diluted chamois acid. Soluble substances in acid will pass into solution, and will not disturb the subsequent stages of processing. It even more will enrich gold-bearing sand.
5. Then, make royal vodka. Mix one part of the concentrated nitric acid and three parts of the concentrated hydrochloric acid. Fill in with solution gold-bearing sand.
6. When gold is dissolved in royal vodka, it will be in the form of tetrakhlorauratny acid. Evaporate solution, at the bottom there will be crystals. At further heating this acid will decay with release of trichloride of gold which in turn at 254 degrees will break up to chlorine and pure gold. Wash the rest with water.