ISOTOPE-EXCHANGE BETWEEN ALKALINE-EARTH METAL HYDROXIDE AND HTO WATERIN THE EQUILIBRIUM STATE

In order to reveal to what extent tritium (H-3 or T) can be incorporat ed into hydroxides, the isotope exchange reaction (OT-for-OH exchange reaction) between each alkaline earth metal hydroxide (M(OH)(2)), wher e M means alkaline earth metal (M = Ca, Sr or Ba) and HTO water was ob served homogeneously at 30 degrees C under equilibrium after mixing. C onsequently, the followings were obtained: (1) a quantitative relation between the electronegativity of each M ion and the ability (of the M ion) incorporating OT- into the M hydroxide can be found and the abil ity is small when the temperature is high, (2) the exchange rate for t he OT-for-OH exchange reaction is small when the electronegativity of the M ion in the M hydroxide is great, (3) as for the dissociation of HTO water, it seems that formula (HTO reversible arrow T+ + OH-) is mo re predominant than the formula (HTO reversible arrow H+ + OT-) when t he temperature is high and (4) the method used in this work is useful to estimate the reactivity of a certain alkaline material.