All About Germain Henri Hess

At the age of three, Hess and his family moved to Russia, where his father had found employment teaching art to the children of an affluent family. Hess graduated from the University of Tartu in 1826, with a medical degree. In school, he excelled in chemistry and geology. After graduation he traveled back to Sweden and studied under Jons Jakob Berzelius, a fellow chemist. The two remained friends and correspondents for the rest of their lives. Upon returning to Russia, Hess went on a geological expedition to the Urals, after which he began a medical practice in Irkutsk. This practice only lasted two years, as in 1830 Hess moved to St. Petersburg. Here, he taught chemistry, and began his research.Hess became a professor at the St. Petersburg Technological Institute, and lived in St. Petersburg for the rest of his life.

1802 - Birth1805 - Moves to Russia1826 - Graduates1826- Meets J.J. Berzelius1830 - Moves to St. Petersburg 1842- law of thermoneutrality1850 - Dies in St. Petersburg

Lasting Impact

While Hess only made two important discoveries in his lifetime, he was a very influential figure in the development of chemistry in Russia. In particular, his textbook entitled Fundamentals of Pure Chemistry was republished seven times, and up until 1861 was considered the standard Russian text in chemistry. Hess' Law is a fundemental equation in thermochemistry to this day.

Culp, B. (2005, September 13). Germain Henri Hess. Retrieved February 24, 2015, from http://www.chemistryexplained.com/Ge-Hy/Hess-Germain-Henri.htmlEric. (2011, August 7). Germain Henri Hess. Retrieved February 24, 2015, from http://deadscientistoftheweek.blogspot.ca/2011/08/germain-henri-hess.htmlGermain Henri Hess. (2015). In Encyclopædia Britannica. Retrieved from http://www.britannica.com/EBchecked/topic/264106/Germain-Henri-Hess

Biography

Hess' Law Explained

St. Petersburg in 1860

Tartu University

All AboutGermain Henri Hess

Geneva in 1860

Accomplishments

Hess was more interested in the theoretical aspects of chemistry than discovering and analysing new substances. This led Hess to investigate the nature of chemical affinity, with particular interest in the heat generated by chemical reactions. Hess experimented with various hydrates of sulfuric acid, and was able to demonstrate that the heat evolved in their formation was always the same, regardless of whether it was a direct reaction or took place in many steps. Realizing the importance of this discovery, Hess continued to study in this vein. In 1842, he proposed the law of thermoneutrality, which states that no heat is evolved by the exchange reaction of neutral salts in aqueous solutions.

Timeline

Jons Jakob Berzelius

References