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We begin as a starting point with the atomic molecular theory. We thus assume that most of the common elementshave been identified, and that each element is characterized as consisting of identical, indestructible atoms. We also assume thatthe atomic weights of the elements are all known, and that, as a consequence, it is possible via mass composition measurements todetermine the molecular formula for any compound of interest. In addition, we will assume that it has been shown by electrochemicalexperiments that atoms contain equal numbers of positively and negatively charged particles, called protons and electronsrespectively. Finally, we assume an understanding of the Periodic Table. In particular, we assume that the elements can be groupedaccording to their common chemical and physical properties, and that these chemical and physical properties are periodic functionsof the atomic number.


The atomic molecular theory is extremely useful in explaining what it means to form a compound from itscomponent elements. That is, a compound consists of identical molecules, each comprised of the atoms of the component elements ina simple whole number ratio. However, our knowledge of these atoms is very limited. The only property we know at this point is therelative mass of each atom. Consequently, we cannot answer a wide range of new questions. We need a model which accounts for theperiodicity of chemical and physical properties as expressed in the Periodic Table. Why are elements which are very dissimilar inatomic mass nevertheless very similar in properties? Why do these common properties recur periodically?

We would like to understand what determines the number of atoms of each type which combine to form stablecompounds. Why are some combinations found and other combinations not observed? Why do some elements with very dissimilar atomicmasses (for example, iodine and chlorine) form very similar chemical compounds? Why do other elements with very similar atomicmasses (for example, oxygen and nitrogen) form very dissimilar compounds? In general, what forces hold atoms together in forming amolecule?

Answering these questions requires knowledge of the structure of the atom, including how the structures of atomsof different elements are different. Our model should tell us how these structural differences result in the different bondingproperties of the different atoms.

Observation 1: scattering of α particles by atoms

We have assumed that atoms contain positive and negative charges and the number of these charges is equal inany given atom. However, we do not know what that number is, nor do we know how those charges are arranged inside the atom. Todetermine the location of the charges in the atom, we perform a "scattering" experiment. The idea is straightforward:since we cannot "see" the atomic structure, then we instead "throw" things at the atom and watch the way inwhich these objects are deflected by the atom. Working backwards, we can then deduce what the structure of the atom must be.

Questions & Answers

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
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.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
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.
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
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
characteristics of micro business
for teaching engĺish at school how nano technology help us
How can I make nanorobot?
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
how can I make nanorobot?
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
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.
what is the actual application of fullerenes nowadays?
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.
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Source:  OpenStax, Concept development studies in chemistry. OpenStax CNX. Dec 06, 2007 Download for free at http://cnx.org/content/col10264/1.5
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