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.
Per Teodor Cleve Per Teodor Cleve (10 February 1840 – 18 June 1905) was a Swedish chemist, biologist, mineralogist, oceanographer, and professor. He discovered the chemical elements holmium and thulium and helped isolate helium from the uranium ore cleveite. Cleve was born in Stockholm and became an assistant professor at the Uppsala University in 1860. He died several months after contracting pleurisy in 1904.