Why does acetone evaporates faster than water?

Why does acetone evaporates faster than water?


water is very polar so the molecules are held together fairly firmly slowing evaporation

acetone is not very polar at all so evaporates easily


It has a lower boiling point, and has a lower surface tension.



acetone boiling point at 56.3 Degree C.

acetone boiling point lower than water which makes it easier to evaporate faster than water.


The atomic structure of acetone is such that the molecules don't stick together because the polarization is equally distributed across the entire surfaces of the molecule. This makes them want to achieve a more natural gaseous state. Water is slightly polarized on one side, making the molecules a bit sticky and more likely to stay around each other rather than go into gas.


It all has top do with the intermolecular forces they each experience.

Firstly, Water. Water is a polar molecule. With this, it experiences strong dipole-dipole interactions with other water molecules. Also, water molecules can hydrogen bond with other water molecules. This is because the hydrogens are bonded to a highly electro negative atom, oxygen. Along with these, it also experiences weaker induced dipole forces and van der Waal's interactions. This explains its boiling point of 100 degrees celsius.

Now, acetone. Acetone, the organic compound, cannot experience the strong hydrogen bonds like in water because is carbonyl oxygen is not bonded to a hydrogen for this to even be possible. The dipole moment created in acetone is also much smaller (O-C bond is less polar than O-H bond) so the dipole-dipole interactions are weaker.

Thus, from this, we can see that water has much stronger intermolecular interactions and so, has a much higher boiling point.