The Dualistic Theory of Chemistry

The early alchemists and natural philosophers believed in the duality of matter —sun and moon male and female sulfur (fixed) and mercury (volatile). When Davy electrolyzed pure potash (KOH) and produced a volatile (female) spirit (oxygen) at the positive pole and an explosive, fixed (male) matter (potassium) at the negative pole, this would have been intuitively obvious to them. 

FIGURE 248. Title page of Jons Jakob Berzelius first book. He reports the isolation of lactic acid in flesh juice (muscle). 

The central tenet of Berzelius world view was the dualistic theory that still pervades our understanding of chemistry—particularly for ionic compounds such as sodium chloride. Briefly, table salt is composed of a positive part (Na ) and a negative part (Cl ). Such dualism was already part of Lavoisier s thinking some 30 years earlierd 

Acid = radical + oxygen Base = metal + oxygen Salt = base + acid 

---