Hermann Franz Moritz Kopp (30 October 1817 – 20 February 1892), German chemist, was born at Hanau, where his father, Johann Heinrich Kopp (1777 - 1858), a physician, was professor of chemistry, physics and natural history at the local lyceum.

After attending the gymnasium of his native town, he studied at Marburg and Heidelberg, and then, attracted by the fame of Liebig, went in 1839 to Gießen, where he became a privatdozent in 1841, and professor of chemistry twelve years later. In 1864 he was called to Heidelberg in the same capacity, and he remained there till his death.

Kopp devoted himself especially to physico-chemical inquiries, and in the history of chemical theory his name is associated with several of the most important correlations of the physical properties of substances with their chemical constitution. Much of his work was concerned with specific volumes, the conception of which he set forth in a paper published when he was only twenty-two years of age; and the principles he established have formed the basis of subsequent investigations in that subject, although his results have in some cases undergone modification.

Another question to which he gave much attention was the connection of the boiling point of compounds, organic ones in particular, with their composition. In addition to these and other laborious researches, Kopp was a prolific writer. In 1843 - 1847 he published a comprehensive History of Chemistry, in four volumes, to which three supplements were added in 1869 - 1875. The Development of Chemistry in Recent Times appeared in 1871 - 1874, and in 1886 he published a work in two volumes on Alchemy in Ancient and Modern Times.

Kopp, in studying heat capacities, found "that the molecular heat capacity of a solid compound is the sum of the atomic heat capacities of the elements composing it; the elements having atomic heat capacities lower than those required by the law of Dulong and Petit retain these lower values in their compounds."

In addition, Kopp wrote (1863) on theoretical and physical chemistry for the Graham-Otto Lehrbuch der Chemie, and for many years assisted Liebig in editing the Annalen der Chemie and the Jahresbericht.

He is not to be confused with another chemist, Emil Kopp.