WJ Bond Theory

Chain Theory

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Chain theory was popular for many years after it was proposed in 1869 by Blomstrand. In 1893 it was challenged by a relative newcomer, Alfred Werner. Werner called his new theory, "coordination theory".
Chain Theory Proposed 1869		Werner introduces his theory 1893

	Jørgensen modifies Chain Theory 1883
		1893 ---------------------------------> 1907 The period of this simulation.

I am not satisfied that the Chain theory is adequate for the formulation of the metal ammines--in fact, I think that it is a confused concept. It does not explain why six ammonia groups always add to metal salts. It also does not always explain the presence of ions when the compounds are dissolved.

Ions were themselves a revolutionary topic in the 1890's. In his 1883 PhD thesis, Arrhenius had introduced the theory of ionization in solution. The existence of charged ions in solution was not uiversally popular and many chemists did not accept the idea.

By 1893, chain theory has been a popular and satisfactory method of formulating the metal ammines. Werner's theory represents quite a break with the past. I see nothing about it that is superior to the chain theory.