Question

Can a droplet of formalin evaporate in midair while falling?

Answer 1

..... Hy friend.....
Yes, a drop of formalin can evaporate while falling. The requirements are:

the atmosphere around the formalin drop must have a low enough formalin vapour pressure (so that the atmosphere must be able to absorb more formalin).

the temperature of the atmosphere around the droplet must be high enough.

the droplets of formalin must be small enough. Smaller droplets have a higher surface area to volume ratio, meaning they can evaporate faster per given mass. Evaporation time τ∝D2τ∝D2where DD is the droplet size

the fall must be long enough in terms of time.

In case you want to increase the speed of gases in the opposite direction to the droplet fall, shows that there is indeed a relationship between wind speed and evaporation rate.
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