The Danish scientist S.P.L. (Soren Peder Lauritz) Sorensen is the man who invented the pH scale (remember those pink and blue strips from your high school chemistry class?)
S.P. L. Sorensen developed the method of measuring acidity and alkalinity in 1909 while studying the effect of ion concentration on proteins. Today the method is hugely important for daily necessities like clean water and medicine.
Sorensen was born in Havrebjerg, Denmark 1868. He studied at the University of Copenhagen with the intention of studying medicine, but went on to have a career as a scientist. Sorensen was the head of the prestigious Carlsberg Laboratory in Copenhagen for 37 years, where he worked alongside his second wife, Margrethe Høyrup Sørensen. He worked in the lab until the year before his death at age 71.
With the interactive feature of today’s Google Doodle, you can learn where common foods fall on the scale.