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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

where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
Ali
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
hey
Giriraj
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
Bhagvanji
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
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
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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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