Izaak Kolthoff, Dutch chemist and academic (b. 1894)
Izaak Maurits (Piet) Kolthoff (February 11, 1894 – March 4, 1993) was an analytical chemist and chemistry educator. He is widely considered the father of analytical chemistry for his large volume of published research in diverse fields of analysis, his work to modernize and promote the field, and for advising a large number of students who went on to influential careers of their own.

Kolthoff's best-known research contribution was the development of the "cold process" for producing synthetic rubber, which he undertook under the U.S. synthetic rubber program during World War II. He was also active in social causes, including promoting world peace and opposing nuclear weapons testing.

Kolthoff received a PhD in chemistry from the University of Utrecht in his native Netherlands. In 1927, he immigrated to the United States, joining the faculty at the University of Minnesota, where he worked for more than 60 years.