Tennessine (Ts) - Element 117
General Characteristics
Tennessine is a synthetic chemical element with the atomic number 117. It is highly radioactive and extremely unstable, with the most stable known isotope, Tennessine-294, possessing a half-life of less than a second. Due to its fleeting existence and the production of only a few atoms at a time in specialized laboratories, the macroscopic physical properties of Tennessine cannot be directly observed. All descriptions of its physical properties are based on theoretical predictions and extrapolations from periodic trends, particularly considering significant relativistic effects on superheavy elements. The element’s name honors the U.S. state of Tennessee, a region with a significant history in heavy element research.
Classification
Tennessine is positioned in Group 17 of the periodic table, placing it in the halogen family, below astatine. However, theoretical calculations suggest that due to strong relativistic effects, its chemical and physical properties are expected to deviate considerably from those of lighter halogens. It is predicted to exhibit pronounced metallic or metalloid-like characteristics rather than behaving as a typical non-metal halogen. Therefore, Tennessine is often classified as a “superheavy halogen” with metallic tendencies, or as a post-transition metal within the p-block.
Predicted Physical Properties
- State of Matter at Room Temperature: Tennessine is predicted to be a solid at room temperature. This prediction follows the general trend observed in Group 17, where elements become increasingly solid with higher atomic mass (e.g., iodine and astatine are solids).
- Color: The color of Tennessine is unknown. If it exhibits metallic character as predicted, it might possess a dark metallic appearance or a silvery-gray luster.
- Texture: Its texture is also unknown. As a predicted solid with potential metallic characteristics, it might be brittle.
- Melting Point: Based on theoretical models, Tennessine is predicted to have a melting point significantly higher than its lighter halogen counterparts, estimated to be in the range of approximately 350 to 550 degrees Celsius. This higher melting point is attributed to the expected increase in metallic bonding contributions.
- Boiling Point: The predicted boiling point for Tennessine is approximately 610 degrees Celsius.