Abstract: The rate constants of Para Bformation reaction have been determined within Zvalues between 0.35 and 1.10 by means of the H₂O₂-SO₂method at 80℃. The reaction has been confirmed a transformation process from Para Ato Para B. The rate constants are inversely proportional to the Zvalues and directly proportional to the contact area of the glass vessel per unit volume of the solution. The reaction has the characteristic of zero-order with the activation energy of 70.72kJ/mol in glass vessel. The rate is negligible in the plastic vessel. According to the characteristics of the transformation reaction, the chemical adsorption-condensation mechanism has been suggested.

Key words: Paratungstate A, Paratung'state B, Kinetics of transformation reaction