TL;博士:亨利定律描述了一个理想的线性关系平衡的低浓度溶质在溶液中,溶质在气相的分压比的解决方案。拉乌尔定律描述理想的线性关系占主导地位的溶剂在溶液的浓度和溶剂的分压在上方的气体混合物。因为水是海洋的主要溶剂,亨利定律不适用。任何从大气中水蒸气溶解在海洋里简单地增加了溶剂。- - - - - -亨利定律描述溶质在纯溶剂的行为。我将引用部分[你引用维基百科文章][1]将一些相关的点。>亨利定律是一个气体定律,指出的溶解气体量>液体正比于其分压高于液体。文章中被忽视的一点是,它假定不同气体的气相混合物是一种理想的——也就是说,他们遵循理想气体定律。这是一个非常好的近似地球大气层。对于理想气体,然后在溶液中浓度与空气中的浓度由亨利定律常数。 The value of the constant depends on how the equation is written and the concentration units used. > Henry's law has been shown to apply to a wide range of solutes in the > limit of infinite dilution (x → 0), including non-volatile substances > such as sucrose. In these cases, it is necessary to state the law in > terms of chemical potentials. For a solute in an ideal dilute > solution, the chemical potential depends only on the concentration. > For non-ideal solutions, the activity coefficients of the components > must be taken into account Henry's law becomes exact at very low concentrations of the solute. At higher concentrations, there is deviation from ideality due to interactions between the dissolved species. This means Henry's law is only used for low-concentration solutes. At the other end, Raoult's law applies. So for H2O in the oceans the water is nearly pure so it behaves as an ideal liquid. In thermodynamic terms the ratio between the water partial pressure at equilibrium in air above the solution (the ocean) and the water partial pressure above pure water times the mole fraction of water in the ocean (the mole fraction is the number of moles of water divided by the total number of moles of the solution - so close to 1 because the ocean is mostly water). If there was absolutely complete ideal mixing between two solutes, say ethanol and water, then Raoult's law would be followed for all mixtures between the two. This is the same as saying the Henry's law constant would be 1 if the concentrations are given in mole fractions. That is not usually the case and the slope of the linear Henry's law region is different. Here is a figure for ethanol water from a more rigorous answer to a [question in chemistry stack exchange][2]. [![https://chemistry.stackexchange.com/questions/89872/what-are-the-key-differences-between-raoult-s-law-and-henry-s-law/90771][3]][3] [1]: https://en.wikipedia.org/wiki/Henry%27s_law [2]: https://chemistry.stackexchange.com/questions/89872/what-are-the-key-differences-between-raoult-s-law-and-henry-s-law/90771 [3]: https://i.stack.imgur.com/eylPd.png
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