52nd International Chemistry Olympiad, Istanbul, TURKEY
Preparatory problems: THEORETICAL
Problem 16. Thermal Springs of Turkey and Sulfur Chemistry Turkey is one of the 7 countries in the world in terms of thermal source richness with almost 1300 thermal springs throughout Anatolia. There are thermal hotels in many cities such as Ankara, Bursa, Balıkesir, Yalova, Erzurum, Sivas and Afyonkarahisar. Afyonkarahisar, located in the Aegean region, is the most famous city in Turkey for its thermal springs. The thermal waters of Afyonkarahisar contain over 42 different minerals and many trace elements. The most concentrated ones are sulfur, calcium, chloride, sodium, and carbonates. Among these minerals, sulfur is important as “nature’s beauty mineral” because the human body needs it to manufacture collagen, which keeps human skin elastic, beautiful, and young looking. Moreover, sulfur is used to minimize the symptoms of many skin diseases including dermatitis, eczema, dandruff, and warts. People with arthritis may obtain pain relief from taking a soothing bath in thermal sulfur springs. Mineral water containing sulfur compounds is also shown to decrease cholesterol and blood pressure. Therefore, sulfur chemistry is an important topic. In this question, you will explore sulfur chemistry by studying its different reactions and compounds.
Hot spring Sulfur is extracted as the element from underground deposits. It has many allotropes and its allotropy is complicated, but the most common sulfur allotrope is the puckered rings of S8 (orthorhombic sulfur, -form). 16.1. Sketch the molecular structure of S8 and indicate whether the molecule has a horizontal mirror plane or not. 110
