Karl Friedrich Mohr (November 4, 1806 – September 28, 1879) was a German chemist famous for his early statement of the principle of the conservation of energy.

At the age of twenty-one he began to study chemistry under Leopold Gmelin, and, after five years in Heidelberg, Berlin and Bonn, he returned with the degree of PhD to join his father's establishment.

He retired from it for a life of scientific leisure in 1857, but at the age of fifty-seven some serious financial losses caused him to become a privatdozent in Bonn.

He invented an improved burette which had a tip at the bottom and a clamp (a 'Mohr's clip'), which made it much easier to use than its predecessors, which were more similar to a graduated cylinder.

[3] His Geschichte der Erde, eine Geologie auf neuer Grundlage (1866) (History of the Earth, a Geology on a New Basis), was also widely circulated.