Hasan, Iraj
AP Chemistry periods 3-4
10/19/14
Introduction to Alchemy: Results and Conclusions
Results
In this lab, only qualitative observations were made in the attempt to make gold from base metals. While heating the pennies in the zinc chloride solution with granular zinc, the zinc appeared to be bouncing upon the surfaces of the pennies. The penny that was more surrounded by the granular zinc appeared to turn silvery faster than the other. The side of the penny facing towards to opening of the beaker was more silvery than the opposite side because it was more exposed to the zinc. Once boiling point was reached and the pennies were removed and rinsed, both appeared to be silver, looking like dimes. While heating one of the pennies in the Bunsen burner, it was observed that the penny turned a bronze-ish color, then bright gold. However, it quickly began to burn and ended up bending in half.
Conclusions
Prior to the experiment, it was hypothesized that gold cannot be produced from base metals by the methods used in this lab. Although the penny became a golden color, its true chemical composition did not include gold in the slightest. After placing two pennies into the zinc chloride solution with granular zinc until boiling point was reached, the zinc metal dissolved and releases electrons that went into the copper and gave it a negative charge. The zinc ions in solution then formed a thin layer of zinc metal upon the penny, giving the coin a silvery color. However, no elemental silver was present. After heating the penny in the Bunsen burner, the zinc diffused into the copper, forming the alloy brass (65-90% copper, 10-35% zinc) on the surface, which incidentally made the penny look like it underwent transmutation to form gold. In reality, no elemental gold was present. Results were compared with one other lab group and were extremely similar. While some of the observations made in this experiment could, in fact, support the hypothesis of a base metal being transmuted into gold, once one studies and thinks about the reactions truly taking place, it becomes evident that gold was not and cannot be produced using these methods. For example, the physical property of gold being soft and malleable is supported by the “gold” penny readily bending in the heat of the Bunsen burner. The golden penny was also lustrous, as gold is. However, many of the observed qualities of the golden penny would also fit into the properties of bronze, which is the actual metal alloy formed in the reaction. Bronze alloys are composed of copper and zinc, which are the two main elements present in this experiment. Conversely, with the reaction and solubility rules in mind, the only way elemental gold could have been produced in this experiment would be from one’s imagination.
Possible errors include overheating the penny and not heating enough on the hot plate. To improve this lab, more trials would lead to a better understanding of the concept of alchemy. This lab provides data to conclude that it is impossible to produce gold from pennies using the methods in this lab because pennies are an alloy of copper and zinc metals, and the other substances they reacted with would in no way result in a substance composed of elemental gold; instead, they would be gold in color.
A Brief Analysis of the Life and Findings of Paracelsus
Paracelsus was born and raised in the village of Einsiedeln in Switzerland. His father, Wilhelm Bombast von Hohenheim, was a German chemist and physician. In 1502 the family moved to Villach, Carinthia where Paracelsus' father worked as a physician, attending to the medical needs of the pilgrims. He received a profound humanistic and theological education by his father, local clerics and the convent school of St. Paul's Abbey in the Lavanttal. At the age of 16 he started studying medicine at the University of Basel, later moving to Vienna. He gained his doctorate degree from the University of Ferrara in 1515 or