08-07 – Germain Henri Hess's BirthdayOn this day back in 1802, Germain Hess was born in Switzerland. Hess would go on to do important work in the field of thermochemistry, the part of chemistry concerned with energy changes in chemical reactions. His work led to the eponymous Hess’s law, explained in the graphic above. Hess also analysed the mineral silver telluride, which was named Hessite in his honour.