THERMAL DECOMPOSITION OF COPPER(II) AND ZINC CARBONATE HYDROXIDES
The ratio of evolved CO2 and H2O during the ther-
mal decomposition of ZCH was determined to be
n(CO2)/n(H2O)=0.664, supporting the reactant compo-
sition of hydrozincate, Zn5(CO3)2(OH)6, and the decom-
position reaction of Eq. (3). Finally, the composition of
ZCH synthesized in the present work was determined as
Zn5(CO3)2(OH)6 from the results of quantitative analy-
ses of evolved CO2 and H2O. The total mass fraction of
evolved CO2 and H2O with reference to the reactant
mass was calculated from the analytical values as
26.5%. The fairly good correspondence to both the ob-
served mass-loss by TG, 26.4±0.4%, and the calculated
mass-loss for Eq. (3), 25.9%, indicate a strictly quantita-
tive relationship of the present analytical procedure for
determining evolved CO2 and H2O during the thermal
decomposition.
positions, which implies strictly quantitative relation-
ship of the present analytical procedure for determin-
ing the amounts of evolved CO2 and H2O during the
thermal decomposition of solids.
Acknowledgements
The present work was supported partially by grant-in-aid for
scientific research (15020242, 15606008, and 16300253).
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