Johannes Nicolaus Brønsted (; 22 February 1879 – 17 December 1947) was a Danish physical chemist, who developed the

Brønsted–Lowry acid–base theory The Brønsted–Lowry theory (also called proton theory of acids and bases) is an acid–base reaction theory which was proposed independently by Johannes Nicolaus Brønsted and Thomas Martin Lowry in 1923. The fundamental concept of this the ...

simultaneously with and independently of Martin Lowry.

Biography

Brønsted was born in

Varde Varde is a Danish city in southwestern Jutland and is the primary city in the municipality of Varde, in Region of Southern Denmark. In 2015 municipality changed its motto to "We in nature" to emphasize its rural atmosphere. The town has an old ma ...

Denmark ) , song = ( en, "King Christian stood by the lofty mast") , song_type = National and royal anthem , image_map = EU-Denmark.svg , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of Denmark , establishe ...

on 22 February 1879. His mother died shortly after his birth and at the age of 14, Brønsted lost his father and moved to Copenhagen with his older sister and his stepmother. In 1897, Brønsted began his studies as a chemical engineer at the Polytechnic Institute in

Copenhagen Copenhagen ( or .; da, København ) is the capital and most populous city of Denmark, with a proper population of around 815.000 in the last quarter of 2022; and some 1.370,000 in the urban area; and the wider Copenhagen metropolitan ar ...

. After his first degree, Brønsted changed fields and received his

magister degree A magister degree (also magistar, female form: magistra; from la, magister, "teacher") is an academic degree used in various systems of higher education. The magister degree arose in medieval universities in Europe and was originally equal to th ...

in chemistry in 1902 from the

University of Copenhagen The University of Copenhagen ( da, Københavns Universitet, KU) is a prestigious public university, public research university in Copenhagen, Copenhagen, Denmark. Founded in 1479, the University of Copenhagen is the second-oldest university in ...

. In 1905, he became an assistant at the Chemical Institute and obtained his doctoral degree in 1908. In the same year, Brønsted became a professor of physical and

inorganic chemistry Inorganic chemistry deals with synthesis and behavior of inorganic and organometallic compounds. This field covers chemical compounds that are not carbon-based, which are the subjects of organic chemistry. The distinction between the two disc ...

at the

. In 1929, Brønsted was a visiting professor at

Yale University Yale University is a Private university, private research university in New Haven, Connecticut. Established in 1701 as the Collegiate School, it is the List of Colonial Colleges, third-oldest institution of higher education in the United Sta ...

. His research gained worldwide recognition, resulting in four

Nobel prize The Nobel Prizes ( ; sv, Nobelpriset ; no, Nobelprisen ) are five separate prizes that, according to Alfred Nobel's will of 1895, are awarded to "those who, during the preceding year, have conferred the greatest benefit to humankind." Alfre ...

nominations, a gold H. C. Ørsted Medal and being appointed as a fellow of the

Royal Society The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, r ...

and a member of the

National Academy of Sciences The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the Nat ...

. Brønsted married Charlotte Warberg, whom he met during his first degree. The couple had four children. In

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the World War II by country, vast majority of the world's countries—including all of the great power ...

, Brønsted's opposition to the

Nazis Nazism ( ; german: Nazismus), the common name in English for National Socialism (german: Nationalsozialismus, ), is the far-right politics, far-right Totalitarianism, totalitarian political ideology and practices associated with Adolf Hit ...

led to his election to the Danish parliament in 1947, but he was too ill to take his seat and died shortly after the election.

Research

Early in his career, Brønsted studied

chemical thermodynamics Chemical thermodynamics is the study of the interrelation of heat and work with chemical reactions or with physical changes of state within the confines of the laws of thermodynamics. Chemical thermodynamics involves not only laboratory measureme ...

and later studied electrolyte solutions and carried out an extensive series of solubility measurements. These measurements led him to establish general laws which were later confirmed when the Debye–Hückel theory was proposed. Brønsted is best known for his work on reaction kinetics, in particular acid–base reactions. In 1923, he recognized that acid–base reactions involved the transfer of a proton, from the acid (proton donor) to the base (proton acceptor). Almost simultaneously and independently, the British chemist Martin Lowry arrived to the same conclusion, thus the name

. Also in 1923,

Gilbert N. Lewis Gilbert Newton Lewis (October 23 or October 25, 1875 – March 23, 1946) was an American physical chemist and a Dean of the College of Chemistry at University of California, Berkeley. Lewis was best known for his discovery of the covalent bond a ...

proposed an

electron The electron (, or in nuclear reactions) is a subatomic particle with a negative one elementary electric charge. Electrons belong to the first generation of the lepton particle family, and are generally thought to be elementary partic ...

ic theory of acid–base reactions, but both theories remain commonly used. Later in his career, Brønsted kept studying reaction kinetics, with a special focus on reactions taking place in non-aqueous solutions. He also developed some work about the effect of molecular size on the thermodynamical properties of hydrocarbons, polymers and colloids. He also worked with the Nobel prize winner George de Hevesy on isotope separation by fractional distillation.

References

{{DEFAULTSORT:Bronsted, Johannes Nicolaus 1879 births 1947 deaths People from Varde Municipality Danish physical chemists University of Copenhagen alumni University of Copenhagen faculty Foreign associates of the National Academy of Sciences