What is the titration invented by the Danish chemist famous for the concept of pH used for?
S. P. L. Sørensen Søren Peder Lauritz Sørensen (9 January 1868 – 12 February 1939) was a Danish chemist, famous for the introduction of the concept of pH, a scale for measuring acidity and alkalinity. He was born in Havrebjerg, Denmark.
Peder Soerensen Peder Sørensen, widely known by his Latinized name, "Petrus Severinus" (1542–1602), was a Danish physician, and one of the most significant followers of Paracelsus. His works include the major treatise "Idea medicinae philosophicae" (Ideal of Philosophical Medicine) (1571), which asserted the superiority of the ideas of Paracelsus to those of Galen. Severinus was a member of Denmark's intellectual elite. His education was supported by the Danish crown and his eventual appointment as royal physician conferred status and authority to his work and opinions. He was a contemporary and intellectual and personal associate of Tycho Brahe who likewise is associated with the evolution of chemistry during the seventeenth century. Daniel Sennert, a professor at Wittenberg wrote in 1619 that most chemical physicians followed the lead of Severinus and even referred to a “Severinian School” of medical theory, which was based on the philosophy of Paracelsus. Scholars including Jole Shackelford and Hiro Hirai ("Le concept de semences dans les théories de la matière à la Renaissance", 2005) have claimed that Severinus was an important predecessor of both Johann Baptista von Helmont and Pierre Gassendi.