The Vespiary

The Hive => Serious Chemistry => Topic started by: Bill clinton on April 18, 2000, 10:52:00 PM

Title: viscosity of fluid
Post by: Bill clinton on April 18, 2000, 10:52:00 PM
HI bees. Can someone please explain the hypothesis of viscosity to their president?
Title: Re: viscosity of fluid
Post by: FreddyFarce on March 07, 2001, 12:59:00 AM
Viscosity describes the flow rate of a liquid. Things that are very runny, for example water and alcohol are highly viscous. Other liquids, such as molasses with slow flow rates, are determined to be less viscous.

Hope this helps!

JUST BECAUSE I TALK ABOUT SOMETHING, DOES NOT MEAN THAT I HAVE ACTUALLY DONE IT, OR PLAN TO DO IT!
Title: Re: viscosity of fluid
Post by: Rhodium on March 07, 2001, 01:25:00 AM
Actually, it is the other way around. The easier a liquid flows the less viscous it is.

I guess it has to do how easily the molecules in the fluid can move around each other. Liquid N2 (small, non-polar molecules) has very low viscosity, and liquid helium-4 at temperatures near absolute zero has NO viscosity(!), which makes it possible for it to flow out of a non-tilted beaker.

The longer a molecule is, the harder it is for them to move around each other, that's why butane (C4H10) is less viscous than gasoline (about C6-C8), which in turn is less viscous than kerosene (even longer carbon chains). If polar groups are attached to the molecule, that makes them stick together, that is why butanol C4H9OH is more viscous than butane, and butanediol HO-C4CH8-OH is even more viscous.

http://rhodium.lycaeum.org (http://rhodium.lycaeum.org)

Title: Re: viscosity of fluid
Post by: PVnRT_NC8 on March 08, 2001, 05:30:00 PM
um let us not forget taht viscosity is often related to things like boyancy boyancy is really neat thing about viscosity usually as things become more viscious they in fact become more or less dennse ussually more deense with colder tempatures

this means that sometimes oil will sink and water will float or the other way around depending on things like tempature and viscosity, now aint that lava lamp looking so cool now?

Amethystium
Title: Re: viscosity of fluid
Post by: Karl on March 09, 2001, 04:22:00 AM
Viscosity does not play a part buoyancy, only so far as how long it would take an object to sink (or surface).

Surface tension however can support more dense materials which would otherwise sink.