Question: At which laboratory was Carsten Olsen employed as an assistant to the Danish chemist who introduced the concept of pH?
Sentence (from "Christen Thomsen Barfoed"): Christen Thomsen Barfoed (June 16, 1815 – April 30, 1899) was a Danish chemist who devised a way to detect monosaccharide sugars in a solution, now known as the Barfoed's test.
Relevant evidence: No