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Foundation

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.

Goals

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

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..
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
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
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 i. OpenStax CNX. Jul 18, 2007 Download for free at http://cnx.org/content/col10263/1.3
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