Background
Hendrik Willem Bakhuis Roozeboom was born on October 24, 1854, in Alkmaar, Netherlands.
University of Leiden, Leiden and The Hague, South Holland, Netherlands
Roozeboom studied at the University of Leiden, where he continued his studies in chemistry (1878-1882). Roozeboom received a doctorate in 1884 with a dissertation on the hydrates of sulfur dioxide, chlorine, bromine, and hydrogen chloride.
A portrait of Bakhuis Roozeboom, H.W. (Hendrik Willem) (1854-1907)
Hendrik Willem Bakhuis Roozeboom (October 24, 1854 – February 8, 1907) was a Dutch chemist who studied phase behavior in physical chemistry.
University of Leiden, Leiden and The Hague, South Holland, Netherlands
Roozeboom studied at the University of Leiden, where he continued his studies in chemistry (1878-1882). Roozeboom received a doctorate in 1884 with a dissertation on the hydrates of sulfur dioxide, chlorine, bromine, and hydrogen chloride.
Hendrik Willem Bakhuis Roozeboom was born on October 24, 1854, in Alkmaar, Netherlands.
After completing a high school in Alkmaar (1872), Roozeboom worked in a laboratory that did research on the composition of foods and water. In 1878 he became assistant to J. M. van Bemmelen, professor of chemistry at the University of Leiden, where he continued his studies in chemistry (1878-1882). Roozeboom received a doctorate in 1884 with a dissertation on the hydrates of sulfur dioxide, chlorine, bromine, and hydrogen chloride; in it, he studied the relationship among the three states of matter (solid, liquid, gas) at different temperatures and pressures.
In 1886 van der Waals brought to Roozeboom’s attention J. W. Gibbs's phase rule (1876), which defines the conditions of equilibrium as a relationship between the number of components of a system C and the number of coexisting phases P, according to the equation F = C + 2 - P, where F is the degrees of freedom or variability of the system. This rule gave Roozeboom the theoretical guide to his investigations on heterogeneous equilibrium, which he began to study in 1882.
After receiving the doctorate, Roozeboom remained at Leiden as an assistant to van Bemmelen. From 1881 to 1896 he also taught at a girls’ high school in Leiden, and in 1890 he was appointed a university lecturer in physical chemistry. In 1896 Roozeboom succeeded van’t Hoff as professor of general chemistry at the University of Amsterdam, where he remained for the rest of his life. In 1880 he became a member of the Koninklijke Nederlandse Akademie van Wetenschappen.
Roozeboom’s importance in science stems from his application of the then little-known phase rule to the study of heterogeneous equilibriums. In his first important publication “Sur les differentes formes de l’equilibre chimique heterogene” (1887), he systematically arranged all the known dissociation equilibriums on the basis of the phase rule according to the number of components and the number and nature of the phases. In many publications Roozeboom used two- and three-dimensional figures to illustrate his theory. With his pupil F. A. H. Schreinemakers, Roozeboom investigated the ternary system hydrogen chloride-ferric chloride-water (1894).
In Amsterdam, Roozeboom made especially systematic studies of heterogeneous equilibriums. He gave much attention to mixed crystals, which provided insight into the homogeneous solid phase. Roozeboom represented all phase equilibriums with pressure-temperature-concentration diagrams. He and his pupils gave pseudosystems (such as tautomeric compounds) a phase-theoretical treatment - for example, the system acetaldehyde-paraldehyde and the system sulfur-chlorine.
Roozeboom’s application of the concept of a homogeneous phase to mixed crystals, gas mixtures, and liquid mixtures, from which a general theoretical treatment of equilibriums became possible, was very important. From it, he derived five types of fusion curves, which were experimentally confirmed by his pupils. Both fusion lines and transition phenomena were observed. Roozeboom’s work profoundly stimulated the systematic and comprehensive investigation of alloys through the practical application of the phase rule to the study of alloys of cadmium and tin and binary and ternary alloys of tin, bismuth, cadmium, and lead. Systems of two optical antipodes and liquid mixed crystals were also studied. All these investigations confirmed Roozeboom’s theory, which was also applied to technical problems, such as the system iron-steel, and to metallurgical and experimental petrographical subjects.
In volume I of Die heterogenen Gleichgewichte vom Standpunkte der Phasenlehre (1901) one-component heterogeneous equilibrium systems were systematically treated. In volume II, part 1 (1904), Roozeboom treated two-component systems that contain only one liquid phase. After his death, the work was completed by his pupils Schreinemakers, E. H. Buchner, and A. H. W. Aten (1911-1918).
Roozeboom always studied simple, generally applicable systems, such as calcium chloride-water and ferric chloride-water, which provide an almost complete illustration of the theory of salt hydrates (1889).
In 1890 Bakhuis Roozeboom became a member of the Royal Netherlands Academy of Arts and Sciences.
Quotes from others about the person
W. D. Bancroft described Roozeboom as having done “far more than anyone else to show the importance and significance of Gibbs’s Phase Rule.”
Hendrik Willem Bakhuis Roozeboom was married to Catharina Elisabeth Wins with whom he had seven children.