Previous works have assumed aqueous electrolyte solutions behave thermodynamically non-ideal. When modeling the RbNO₂-H₂O system, it was found that the enthalpy of liquification was zero, which would be a characteristic of an ideal system. Plotting the water mole fraction versus the water activity confirmed that this system was almost ideal (just 5% difference at 62.3 molal). RbNO₂ solutions thus provide insight into ideality in aqueous solutions. An important characteristic of RbNO₂ that may account for the ideality may be that RbNO₂’s attraction for water is nearly identical as the attraction of water to other water molecules.

中文翻译：

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亚硝酸Rub水溶液在0.3至62.3摩尔浓度之间的（几乎）理想热力学

以前的工作假设电解质水溶液在热力学上表现不理想。当对RbNO ₂ -H ₂ O系统建模时，发现液化的焓为零，这将是理想系统的特征。绘制水的摩尔分数与水活度的关系图证实了该系统几乎是理想的（在62.3 molal下仅有5％的差异）。因此，RbNO ₂溶液可洞悉水溶液的理想性。RbNO ₂可能解释理想性的一个重要特征可能是，RbNO ₂对水的吸引力几乎与水对其他水分子的吸引力相同。