mnething new from the b o ~ t Oxidation Reduction S o m e t h i n g New from the Past, in t h e M a y 1981 issue of (58,404 ), carried references to multiTHIS JOURNAL colored titrations using solutions of vanadium compounds. 'I'hese titrations a r e interesting and serve a s wncrete examples to aid students in learning about the redox concept. Here a r e some additional references, "Oxidation States of Vanadium," J. M. Davis, J. CHEM.
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variation on the same theme. Hisvariation is based on the following equation far the reaction: 3NzH4
+ 2 Br- + 6Hz0
Latimer says that "The student is faced with the problem of identifying not only the hydrozine oxidation products (Nz) through the staichiametry but also the bromate reduction product (bromide). . . He isalso offered a chance to speculate on the actualmechanism for the reaction which involves the reduction of Molvhdenum IVI) to Mulybdrnum r V ) (blue) by hydro,inrand rhc oridnrmn