Harold Urey was an American physical chemist born on April 29, 1893, in Walkerton, Indiana. He is best known for his work on isotopes, particularly the discovery of deuterium, a stable isotope of hydrogen. Urey's research significantly advanced the field of chemistry and contributed to our understanding of atomic structure. In 1934, Urey was awarded the Nobel Prize in Chemistry for his contributions to isotope separation techniques. He also played a crucial role in the development of the atomic bomb during World War II as part of the Manhattan Project. Urey's work laid the foundation for various scientific advancements in both chemistry and physics.