Magnetic titrations

Magnetic titrations using a new titration cell and procedure are described. The paramagnetism of a hexammine nickel nitrate solution decreases linearly upon the addition of cyanide up to the endpoint (complete formation of Ni(CN)₄^2-) ; there is no evidence of the formation of intermediate complexes. Intermediate complexes are evident in the titrations of iron(II) with 1,10-phenanthroline and with 2,2'-bipyridyl; log K₁ values, calculated from the magnetic data, are 6.0 and 5.0 respectively.