Frankland, Sir Edward

(1825–99) British organic chemist: originator of the theory of valence.

Frankland was apprenticed to a druggist in Lancaster for 6 years in an ill-advised attempt to enter the medical profession. Guidance from a local doctor led him to study chemistry under Lyon Playfair (1819–98) at the Royal School of Mines in London (1845). He later studied with at Marburg and at Giessen. At 28 Frankland became the founding professor of chemistry at the new Owens College (1851–57) that became the University of Manchester. He moved to St Bartholomew’s Hospital, London (1857); the Royal Institution (1863) and the Royal School of Mines (1865).

He prepared and examined the first recognized organometallics, the zinc dialkyls. In his view, their reaction with water gave the free alkyl radicals (in fact, the corresponding dimeric alkanes). Vastly more significant was his later recognition, after thinking about a range of compounds, of numerical, integral limitations in atomic combining power: the theory of valence–this being the number of chemical bonds that a given atom or group can make with other atoms or groups in forming a compound. He used the word ‘bond’ and modern graphic formulae (Frankland’s notation) and through these ideas did much to prepare foundations for modern structural chemistry. He also made major contributions to applied chemistry, notably in the areas of water and sewage purification–paramount requirements for good public health.