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What do the deviations from ideality tell us about the gas particles? Starting with very low density andincreasing the density as in , we find that, for many gases,the value of P V n R T falls below 1. One way to state this result is that, for a given value of V , n , and T , the pressure of the gas is less than it would have been for an ideal gas. This must be theresult of the interactions of the gas particles. In order for the pressure to be reduced, the force of the collisions of theparticles with the walls must be less than is predicted by our model of an ideal gas. Therefore, the effect of the interactions isto slow the particles as they approach the walls of the container. This means that an individual particle approaching a wall mustexperience a force acting to pull it back into the body of the gas. Hence, the gas particles must attract one another. Therefore, theeffect of increasing the density of the gas is that the gas particles are confined in closer proximity to one another. At thiscloser range, the attractions of individual particles become significant. It should not be surprising that these attractiveforces depend on what the particles are. We note in that deviation from the Ideal Gas Law is greater for ammonia than for nitrogen, and greater for nitrogen than for helium. Therefore,the attractive interactions of ammonia molecules are greater than those of nitrogen molecules, which are in turn greater than thoseof helium atoms. We analyze this conclusion is more detail below.

Continuing to increase the density of the gas, we find in that the value of P V n R T begins to rise, eventually exceeding 1 and continuing to increase. Under theseconditions, therefore, the pressure of the gas is greater than we would have expected from our model of non-interacting particles.What does this tell us? The gas particles are interacting in such a way as to increase the force of the collisions of the particleswith the walls. This requires that the gas particles repel one another. As we move to higher density, the particles are forcedinto closer and closer proximity. We can conclude that gas particles at very close range experience strong repulsive forcesaway from one another.

Our model of the behavior of gases can be summarized as follows: at low density, the gas particles aresufficiently far apart that there are no interactions between them. In this case, the pressure of the gas is independent of the natureof the gas and agrees with the Ideal Gas Law . At somewhat higher densities, the particles are closer together and the interactionforces between the particles are attractive. The pressure of the gas now depends on the strength of these interactions and is lowerthan the value predicted by the Ideal Gas Law . At still higher densities, the particles are excessively close together, resultingin repulsive interaction forces. The pressure of the gas under these conditions is higher than the value predicted by the Ideal Gas Law .

Observation 3: boiling points of simple hydrides

The postulates of the Kinetic Molecular Theory provide us a way to understand the relationship between molecular properties and the physical properties of bulk amounts ofsubstance. As a distinct example of such an application, we now examine the boiling points of various compounds, focusing onhydrides of sixteen elements in the main group (Groups IV through VII). These are given here .

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, General chemistry ii. OpenStax CNX. Mar 25, 2005 Download for free at http://cnx.org/content/col10262/1.2
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