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Liquid aerosols are known to be relatively stable.

However, given their immense surface area and tiny volume, we would expect them to rapidly vanish by evaporation.

Why are liquid aerosols unexpectedly stable to evaporation?

Ritesh Singh
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2 Answers2

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Imagine an aerosol that consists of some solid that is dissolved in water. AT the surface of such a droplet, the water evaporates and the remaining material at the "skin" of the droplet is concentrated in that solid, which inhibits diffusion of the water inside the bulk of the droplet to the skin.

In this way, the evaporation rate of the droplet gets dramatically slowed down relative to that of a droplet of pure water.

Now consider an aerosol consisting of a mixture of water and a substance like glycerin. The presence of the glycerin depresses the vapor pressure of the water because the glycerin molecule "enjoys" the company of nearby water molecules. Here again, a glycerin-rich skin forms on the aerosol droplet, interfering with water diffusion through the skin. Both effects slow down the evaporation rate of the aerosol droplet.

niels nielsen
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Very good and intriguing question indeed. The reason in the liquid particles are a colloid and not only liquids, which affects their properties. The main reason behind this is the presence of nanoparticles which give the colloidal matter exceptional stability and it doesn't evaporate easily.

Find more here (literally, lot more) -

https://www.nature.com/articles/s41598-021-88510-2

Please verify if it helps.

Ritzthephysibeast
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