Harold Clayton Urey Nobel Prize in Chemistry, 1934 Country: USA

Biography of Harold Clayton Urey

Harold Clayton Urey was an American physicist and physical chemist, known for his contributions to the field of isotope separation and the discovery of deuterium. He was awarded the Nobel Prize in Chemistry in 1934 for his discovery of heavy hydrogen.

Early Life and Education:
Harold Urey was born to Samuel Clayton Urey and Cora Rebecca Reinzel. His father, a minister and school teacher, passed away when he was six years old, and his mother remarried. Urey struggled with his studies, but managed to graduate from high school in 1911. He then attended the University of Montana, where he studied zoology and chemistry. In 1914, he received a bachelor's degree in zoology and began working as a research chemist at Barrett Chemical Company in Philadelphia.

Career and Discoveries:
In 1919, Urey returned to the University of Montana as a chemistry teacher. Two years later, he received a scholarship to become a graduate student at the University of California, Berkeley. After earning his PhD in chemistry in 1923, he received a fellowship from the American-Scandinavian Foundation to study at the Institute for Theoretical Physics in Denmark, under the supervision of Niels Bohr.

Upon his return to the United States in 1924, Urey joined the faculty of Johns Hopkins University in Baltimore, Maryland, where he conducted research on thermodynamics, atomic and molecular structure, and atomic spectra. In collaboration with A.E. Ruark, he summarized the development of quantum chemistry in their book "Atoms, Molecules and Quanta" published in 1930.

In 1929, Urey became an adjunct professor of chemistry at Columbia University in New York, under the guidance of renowned physicist-chemist Gilbert Newton Lewis. It was Lewis who inspired Urey to investigate the existence of hydrogen isotopes. Urey devised a method to separate hydrogen isotopes using fractional distillation, and in 1931, he discovered deuterium, the heavy isotope of hydrogen. He named it "deuterium" from the Greek word meaning "second," as it was the second lightest atom after hydrogen. In 1934, Urey was awarded the Nobel Prize in Chemistry for his discovery.

During World War II, Urey participated in the Manhattan Project, where he led a laboratory dedicated to isotope separation. After the war, he left Columbia University and became a distinguished professor at the Institute for Nuclear Studies at the University of Chicago. Urey warned about the dangers associated with nuclear weapons, but later supported the development of the hydrogen bomb.

Contributions to Science:
Urey's work extended beyond isotope separation. He applied the principles of isotope chemistry to various fields of science. He developed a "thermometer" to calculate past climate changes by measuring oxygen isotope ratios in fossils. He also proposed a theory, known as the Cosmochemical Theory, to explain the origin and prevalence of isotopes in the universe. In addition, Urey's research on the formation of the Solar System and the origins of life paved the way for the field of cosmochemistry. His experiments demonstrated that natural amino acids can be formed in prebiotic conditions, contributing to our understanding of the origins of life on Earth.

Later Life and Legacy:
In 1958, Urey became a professor at the University of California, La Jolla, where he worked until 1970. In the 1960s, he advocated for the integration of scientific research with the American space program. He was particularly interested in studying the composition of lunar soil and had the opportunity to analyze samples brought back from the moon.

Harold Urey was described by his colleagues as a deeply contemplative individual, open to new ideas despite his sometimes combative conversational style. His home was known for its hospitality, and he had diverse interests ranging from Greek and Indian sculpture to gardening.

In addition to his scientific achievements, Urey authored several books, including "The Planets: Their Origin and Development" (1952) and "Some Cosmochemical Problems" (1963).

Harold Clayton Urey's contributions to isotope chemistry, thermodynamics, and the origins of life have made him one of the most influential scientists of the 20th century.