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Why should these materials, whose molecules do not seem all that different, behave so differently? What are the important characteristics of these molecules that produce these physical properties?

One of our first efforts at making a connection between molecular properties and macroscopic properties is the development of the Kinetic Molecular Theory. Among the very most important concepts in Chemistry is that atoms and molecules are constantly moving. These movements have a lot to do with how and when the atoms and molecules react with each other. Also among these very important concepts is that the movements of atoms and molecules are related to their temperature. We shall see that a higher temperature corresponds to faster molecules with more energy. Knowing this will help us understand a lot of Chemistry, including how chemical reactions are affected by temperature and energy.


Since we wish to relate macroscopic properties to molecular properties, it is worth remembering what observations and conclusions we have already made about each type of property. In this study, we will focus mainly on the observations of gases which led us to the Ideal Gas Law. We will assume that we have made measurements of the pressure of a gas under different conditions. From these, we know that the pressure of a fixed sample of gas is inversely proportional to the volume in which the gas is contained, meaning that if we reduce the volume of the gas by compressing it, the pressure will rise. In a similar way, we know that the pressure of a fixed sample of gas in a fixed volume will increase in proportion to the temperature, provided that we measure the absolute temperature in Kelvin. And finally, the pressure of the gas kept at fixed temperature is proportional to the “particle density” of the gas, which is the number of gas particles (atoms or molecules) divided by the volume of the container.

We have also learned a great deal about molecular properties that will be useful in this Concept Development Study. We know that different atoms have different electronegativities and that, as a result, when these atoms are bonded together, the electron pair sharing is not equal. This can cause the molecule to have a molecular dipole moment. We also know about the geometries of molecules and that a symmetric molecule may not have a dipole moment even if the bonds in the molecule are polar.

There are a few results from Physics which are important to our work. The first of these is that pressure P is the force exerted F divided by the area A on which it is exerted:

P = F A

This sounds complicated but is actually commonly observed. Think of the differences you see when force is applied to a small area, like the head of a nail, instead of being applied over a large area. For example, a stack of books piled on a desk creates a downward force due to gravity, but that force is applied over a large area, which is the size of the bottom book in the stack. This means that it does not generate that much pressure, so the books have no effect on the desk. However, if the stack of books is somehow piled on top of a sharp nail, the pressure created is very high because the force of gravity has been applied to a very, very small area, namely the point of the nail. This high pressure means that the nail may penetrate the surface of the desk. The force applied in either case is the same, but the pressure is quite different when the stack of books is placed on the nail.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
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..
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
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.
yes that's correct
I think
Nasa has use it in the 60's, copper as water purification in the moon travel.
nanocopper obvius
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
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
analytical skills graphene is prepared to kill any type viruses .
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
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
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
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Source:  OpenStax, Concept development studies in chemistry 2013. OpenStax CNX. Oct 07, 2013 Download for free at http://legacy.cnx.org/content/col11579/1.1
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