Hans Christian Ørsted was a Danish chemist and physicist. He was the first person to discover that electric currents can be used to create magnetic fields. His discovery was the first relationship found between magnetism and electricity. Oersted, the unit of the auxiliary magnetic field H, is named in his honor.
Jens C. Skou was a Danish biochemist best known for his work in the field of animal cells. Along with Paul D. Boyer and John E. Walker, he was jointly awarded the Nobel Prize in Chemistry in 1997. He had a brilliant academic career and remained active well into his 90s. He died at the age of 99.

Danish chemist and astronomer Ejnar Hertzsprung is perhaps best remembered for his unique method of classification of stars by their spectral type. His contributions include the Hertzsprung-Russell diagram. He also worked as a senior astronomer at the Potsdam observatory and headed the university observatory at Leiden.
Danish organic chemist William Christopher Zeise initially aspired to study medicine but later switched to chemistry. He prepared one of the world’s first organometallic compounds, Zeise’s salt, and conducted pathbreaking research in the field of organosulfur chemistry. His achievements got him knighted by the Danish monarch.

Hans Peter Jørgen Julius Thomsen was a Danish chemist best remembered for his hypothesis, the Thomsen–Berthelot principle. One of his books on systematic research in thermochemistry was translated into English by British chemist Katherine Alice Burke. Hans Peter Jørgen Julius Thomsen also served as a professor at the University of Copenhagen.