Schwarzenbach was born and grew up in Horgen, Switzerland. He studied chemistry at the ETH Zurich and graduated in 1928 with his dissertation Studien über die Salzbildung von Beizenfarbstoffen (Studies on the formation of pickling salt dyes). From 1930 to 1955 he was a lecturer and later professor of special inorganic and analytical chemistry at the ETH Zurich. He retired in 1973.