The thermodynamic solubility product of amorphous magnesium carbonate (AMC) was studied at room temperature. The samples had been prepared at pH 8.78 and 9.37, where the particle size was 58 ± 11 nm and 49 ± 9 nm, respectively. Solid‐state NMR measurements showed that the former contained a minute amount of bicarbonate species, whereas we did not detect any for the latter. While the AMC sample prepared at higher pH exhibited a one‐step decomposition at 413°C, the one at lower pH decomposed in two steps at 425 and 510°C. The solubility products of AMC prepared at two pH are statistically identical and the average value is estimated to be 6.3 × 10⁻⁶.

中文翻译：

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无定形碳酸镁的溶解度积

在室温下研究了无定形碳酸镁（AMC）的热力学溶解度产物。在pH 8.78和9.37下制备样品，其粒径分别为58±11 nm和49±9 nm。固态NMR测量表明，前者含有微量的碳酸氢根物质，而我们没有发现后者。在较高pH下制备的AMC样品在413°C时会发生一步分解，而在较低pH下的那一步会在425和510°C下分两步分解。在两个pH值下制备的AMC的溶解度产物在统计学上是相同的，其平均值估计为6.3×10 ^-6。