Amorphous silica solubilities—I. Behavior in aqueous sodium nitrate solutions; 25–300°C, 0–6 molal |
| |
Authors: | William L Marshall |
| |
Institution: | Chemistry Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, U.S.A. |
| |
Abstract: | The solubility of amorphous silica was obtained in aqueous sodium nitrate solutions up to six molal and at temperatures from 25 to 300°C. It was expected that solubilities in aqueous sodium chloride solutions would be similar. At 25°C, the solubility of amorphous silica is lowered from that in water to 0.00086 m in 6.12 m sodium nitrate, or a decrease of 60%. At 300°C, the corresponding decrease is only 27% from a solubility of 0.0269 m in H2O. From the change in solubility with temperature at a given constant molality of sodium nitrate, the molal heat of solution over the range, 100 to 300°C, increases from + 2.93 kcal mol?1 in water to + 3.64 kcal mol?1 in 6m sodium nitrate. The value approaches a constant of +3.8 kcal mol?1 as sodium nitrate approaches saturation at 10.8 molal. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|