Vapor pressure and hysteresis in the graphite-bromine system

✍ Scribed by T. Sasa

• Publisher: Elsevier Science
• Year: 1973
• Tongue: English
• Weight: 544 KB
• Volume: 11
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(73)90308-4

✦ Synopsis

Vapor pressure-composition diagram of the graphite-bromine system shows continuous changes in composition between the definite stages. It also shows a large hysteresis in the process of bromination-debromination. X-ray studies show that an intermediate compound at a composition between definite stages possesses a structure composed of microdomains of either of the two stages. The vapor pressure of the initiation of decomposition of CsBr has practically the same value as that of the initiation of bromination of C,,Br, which is believed to give the equilibrium decomposition pressure of C,Br. The decomposition pressure measurements at temperatures between 15 and 27°C gave the standard heat of reaction -10.2 kcal.mol-' and the standard entropy change of reaction -29.9cal.K-' mol-'. The structural transformation and the hysteresis phenomena in the graphite-bromine system are interpreted assuming that the compound possesses a conglomerate structure of microdomains.