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After the odor has dissipated, repeat the experiment twice.

Using Excel plot the data in distance traveled versus time. Obtain a least squares fit (R value) for this data and determine from it the rate of diffusion of Carvone in meters per second. Create a graph for each trial. Calculate the average of the rates for the three trials. Calculate the root mean square speed of carvone molecules at 25C. Your TA will help you with this equation. Compare the result with the diffusion rate you measured. If they are significantly different, offer an explanation. Would the diffusion take place faster in a vacuum?

Note: You should spend no more than one-half hour preparing the plots. Please stagger yourselves so that everyone has an opportunity to get to the computer stations.

Gas laws in a soda can:

Pour 15 mL of water into an aluminum soda can. Set the can on a hot plate and turn on to a high temperature setting. While the can water heats, fill a 1000-mL beaker with cold water (You may have a metal tin set out for this purpose). Continue heating the can until the water inside boils vigorously and until steam escapes from the mouth of the can for about 20 seconds.

Using the hot grips to grip the can near the bottom, quickly lift the can from the burner and invert (so water covers the mouth of the can) it in the beaker of cold water. Describe what happens. Explain why it happens. You may repeat this experiment using a second soda can if you wish. Why is it necessary to invert the can in the water? What would happen if a rigid container were used?

 Balloon in liquid nitrogen:

Review the safety notes above regarding the handling of liquid nitrogen.

Inflate a balloon and tie the end (Several balloons may have already been inflated and tied). Using tongs, place the balloon in a Dewar flask containing liquid nitrogen. After the balloon stops changing size, remove it from the Dewar and allow it to warm to room temperature. Observe and record the changes (you should be able to measure the radius and estimate volume).

Estimate the size of the balloon in liters. What is the pressure inside the balloon before it is placed in the liquid nitrogen? What is the pressure inside the balloon after it is placed in the liquid nitrogen? Use the ideal gas law to calculate the percent change in volume expected on going from room temperature to liquid nitrogen temperature. Is the volume of the cold balloon consistent with what you calculated, or is it larger or smaller? Suggest an explanation for your observation. Explain all of your observations in detail using the kinetic molecular theory of gases. How does the liquid nitrogen cool the gas in the balloon?

Tygon tube in liquid nitrogen:

Review the safety notes above regarding the handling of liquid nitrogen. Place a 2 foot long tygon clear tube in a Dewar with liquid nitrogen. Observe what happens and explain.

Balloon in a flask:

Place about 5 mL of water in a 125-mL Erlenmeyer flask. Heat the flask on a hot plate until the water boils down to a volume of about 1 mL. Meanwhile, inflate a balloon and then let the air out (this may not be necessary if balloons on table have been previously used). Remove the flask from the heat, hold it with a towel, and immediately place the open end of the balloon over the mouth of the flask. Observe the effect as the flask cools. Can you get the balloon back out again? If you can, How?

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Honors chemistry lab fall. OpenStax CNX. Nov 15, 2007 Download for free at http://cnx.org/content/col10456/1.16
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