[ROSETTA]

Hi, what is the order of viscosity for the following solvents
acetonitrile, methanol, water, thf
Thanks rosie

[agrobert]

What do you think?  What physical properties play a role in viscosity? hydrogen bonding? density?

Why not search Wikipedia?  The viscosities are listed for common chemicals.

[ROSETTA]

Hi, i dont think density and viscosity are related.  Density remains the same if a substance is heated, but viscosity changes.  However, I have just seen a website that mentions the hildebrand constant and that is dependant on volume which is indirecly related to density.  Therefore, in answer to your question, i dont know

Viscosity does depend on hydrogen bonding though.  Molecules that hydrogen bond are much more viscous than those that don't

I did look up wikipedia and water is more viscous than methanol, there is no value reported for acetonitrile, however, based on the idea of hydrogen bonding, I think that methanol will be more viscous than acetonitrile.
I have just did a search and found that this is indeed correct.
Thank you for your help
This is a good way to learn,
All the best
Rosie

[Borek]

Density remains the same if a substance is heated

It doesn't. Why natural water tanks don't freeze to the bottom, thus allowing fish to survive throughout winter?