-Who were the main characters in the development of the atom?
Bohr, Thompson, Rutherford, and Dalton were the main characters in the development of the atom.
-Why were they vital to the development of the atom?
Democritus was the guy who made up the 4 element theory. That everything was made out of.
Dalton formed the atomic theory, which states that all matter is composed of tiny, indestructible particles called atoms that are all alike and have the same atomic weight. Thompson discovered the electron and developed the plum-pudding model of the atom. Rutherford used the results of his gold-foil experiment to state that all the mass of an atom were in a small positively-charged ball at the center of the atom. Bohr stated that the electrons moved around the nucleus in successively large orbits. He also presented the Bohr atomic model which stated that atoms absorb or emit radiation only when the electrons abruptly jump between allowed, or stationary, states.
-What made them different if anything?
Well Dalton was color blind while doing all his research and alter went onto publish “Extraordinary facts relating to the vision of colours” They were all different and uniquely smart and will always be known for discovering the basic building blocks of matter.
-Think about your lessons in history and discuss how the time period that they lived in determined the outcome of their discovery/ or how it influenced those individuals to be the names that we know today (aka did it matter where they grew up or if they had money?)
They were definitely were handicapped by the technology of their time, but theypersevered through and brought us one of the most important discoveries in science history. Yes it might have helped if they had plenty of money to back them up but they probably would have ended up with the same results just a shorter period.
-Why do we consider the atomic theory still a theory? What are the new developments?
Dalton's atomic theory is still only but a theory because not all of his accusations can’t be scientifically tested and proven.
-Why does it matter that we understand the structure of the atoms?
They are the basic building blocks of matter.
Wednesday, September 29, 2010
Tuesday, September 28, 2010
Wesley Barnhill
Democritus-had a theory of the atomic nature of the physical world, developed from that of Leucippus, is known only through the works of critics of the theory such as Aristotle and Theophrastus. It resolved the question of how a world evidently in a state of flux could nevertheless have an underlying nature that was eternal and unchanging. By positing infinitely small things that remained the same but formed different combinations with each other, Leucippus initially, and Democritus in greater detail, managed to answer the question in a way that has been subject to increasingly successful elaboration ever since. One can trace the physical theory of atoms through Epicurus, Lucretius, and Galileo to modern times.
John Dalton- The English teacher, chemist, and physicist , b. Sept. 6, 1766, d. July 27, 1844, is best known for developing the ancient concept of atoms into a scientific theory that has become a foundation of modern chemistry. He considered himself primarily a teacher and earned his living by teaching and lecturing until 1833, when he was awarded an annual civil pension. A self-taught experimenter, he devised simple but effective apparatus for his well-planned tests. Although authors have emphasized the crudeness of his results, many of his data are remarkably accurate.
http://library.thinkquest.org/15567/bio/index.html
John Dalton- The English teacher, chemist, and physicist , b. Sept. 6, 1766, d. July 27, 1844, is best known for developing the ancient concept of atoms into a scientific theory that has become a foundation of modern chemistry. He considered himself primarily a teacher and earned his living by teaching and lecturing until 1833, when he was awarded an annual civil pension. A self-taught experimenter, he devised simple but effective apparatus for his well-planned tests. Although authors have emphasized the crudeness of his results, many of his data are remarkably accurate.
Sir Joseph John Thomson- b. Dec. 18, 1856, d. Aug. 30, 1940, is universally recognized as the British scientist who discovered and identified the electron. At the age of 27 he succeeded (1884) Lord Rayleigh as professor of physics at Trinity College, Cambridge, and was named director of its Cavendish Laboratory in the same year, continuing in that position until 1919. Thomson demonstrated (1897) that cathode rays were actually units of electrical current made up of negatively charged particles of subatomic size. He believed them to be an integral part of all matter and theorized a model of atomic structure in which a quantity of negatively charged electrons was embedded in a sphere of positive electricity, the two charges neutralizing each other. For these investigations he won (1906) the Nobel Prize for physics; in 1908 he was knighted.
Rutherford made his greatest discovery in 1909. Shortly after his move to Manchester, he found that a few alpha particles, when bombarding thin metal foils, were deflected from their incident beam through more than 90 deg. "It was almost as incredible," Rutherford later responded in a now-classic statement, "as if you fired a fifteen-inch shell at a piece of tissue paper and it came back and hit you." Early in 1911 he finally announced his version of the structure of the atom: a very small, tightly packed, charged nucleus sprinkled with opposite charges in the mostly empty surrounding void. The deflected alpha particles were those that had come into close proximity with the nucleus and had rebounded in various oblique directions. About the time that Rutherford moved (1919) to Cambridge to succeed Thomson as director of the Cavendish Laboratory, he discovered artificial disintegration--the artificial splitting of the atom--a signal discovery that presaged his entry into the field of nuclear physics. Members of his Cavendish team discovered the neutron and the disintegration phenomena produced by artificially accelerated particles.
Niels Henrik David Bohr- b. Oct. 7, 1885, d. Nov. 18, 1962, is known primarily for his pioneering work in the field of atomic theory. Bohr was born in Copenhagen and was educated at the University of Copenhagen at the time when Max Planck had just begun the development of Quantum Mechanics. After completing his dissertation on the electron theory of metals in 1911, Bohr went briefly to Cambridge and then on to Manchester, England. There he worked under Ernest Rutherford, who in 1911 had published the theory that the atom consisted of a central nucleus orbited by electrons. The problem with this model was that, according to classical electrodynamic theory, the electrons should radiate and therefore lose energy and spiral into the nucleus.
The men that helped dig deeper into the research of the atom were vital to science because they introduced a whole new world to science. The more scientists researched the atom the found out how much the atom influences our everyday lives. These influences have helped from the invention of the atomic bomb to precision surgeries.
The time in history had many things to do with how these scientists took their research to the next level. Growing up in the industrial revolution probably had a huge influence on what and how the scientists took their work. Being apart of that time frame pushed for harder work to be done and they had the tools to do what they needed to do.
1) All matter is made of atoms. Atoms are indivisible and indestructible.
2) All atoms of a given element are identical in mass and properties
3) Compounds are formed by a combination of two or more different kinds of atoms.
4) A chemical reaction is a rearrangement of atoms.
Modern atomic theory is, of course, a little more involved than Dalton's theory but the essence of Dalton's theory remains valid. Today we know that atoms can be destroyed via nuclear reactions but not by chemical reactions. Also, there are different kinds of atoms (differing by their masses) within an element that are known as "isotopes", but isotopes of an element have the same chemical properties.
http://www.iun.edu/~cpanhd/C101webnotes/composition/dalton.htmlhttp://library.thinkquest.org/15567/bio/index.html
atoms
The invention of the atom is very important. Democritus and John Dalton played a role in the atom. Democritus came up with the idea of the atom. He believed that if you break something down till it can't be broken anymore that the end result was an atom. This thought didn't last too long. For the next 2000 years there was no further explorations of the atom. John Dalton had started doing experiments in the 1800's. He didn't know the structure of the atom but he knew he was onto something.
Monday, September 27, 2010
Andee Fonseca
Democritus, Leucippus, Dalton, Bohr, JJ Thomson, and Rutherford are a few of the many intelligent scientists that contributed to the development of the atom.
Why were they vital to the development of the atom?
Democritus knew that if you took a stone and cut it in half, each half had the same properties as the original stone. He reasoned that if you continued to cut the stone into smaller and smaller pieces, at some point you would reach a piece so tiny that it could no longer be divided. Democritus called these infinitesimally small pieces of matter atomos, meaning "indivisible." He suggested that atomos were eternal and could not be destroyed. Democritus theorized that atomos were specific to the material that they made up. It is said that another scientist, Leucippus, helped him develop this theory; though, there is speculation on whether that statement is true or not.
Through his observations of morning fog and other weather patterns, Dalton realized that water could exist as a gas that mixed with air and occupied the same space as air. Solids could not occupy the same space as each other; for example, ice could not mix with air. So what could allow water to sometimes behave as a solid and sometimes as a gas? Dalton realized that all matter must be composed of tiny particles.
In 1913, Bohr published a theory about the structure of the atom based on an earlier theory of Rutherford's. Rutherford had shown that the atom consisted of a positively charged nucleus, with negatively charged electrons in orbit around it. Bohr expanded upon this theory by proposing that electrons travel only in certain successively larger orbits. He suggested that the outer orbits could hold more electrons than the inner ones, and that these outer orbits determine the atom's chemical properties.
These men were determined scientists that set out to understand the world better. While one maybe improved on a previous scientists theory, another one may have created his own theory. Also, the scientists different ways of thinking helped them come up with different theories concerning the atom. As a whole, these theories are combined to explain what we know of the atom present day. The earlier scientists figured out the atom logically instead of through physically through experimentation like the later scientists.
Democritus and Leucippus had to have great understanding and insight on the way the world works to be able to come up with such complex theories with no way to be sure that they were right and no proof to prove their thoughts. Technology and the advantage of having previous theories to help them definitely put later scientists at an advantage over the earlier ones. They still had to work hard to find out information about the atoms, but they were able to utilize technology and build on a previous foundation, whereas the previous scientists basically had to start out from scratch by just pondering the ways of the world. It's incredible that they were able to come up with such complex theories just by thinking deeply about something.
The atomic theory is still a theory not only because it has a few mistakes and it is not completely proven, but also because it is not complete and their are things still being discovered about the atom.
It is important that we understand the structure of the atom because everything is made out of atoms; also, by understanding the structure of it, we may be able to better understand it's capabilities, such as the fact that splitting an atom causing a mass explosion. There still may be more that an atom can do that we haven't discovered yet.
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Why were they vital to the development of the atom?
Democritus knew that if you took a stone and cut it in half, each half had the same properties as the original stone. He reasoned that if you continued to cut the stone into smaller and smaller pieces, at some point you would reach a piece so tiny that it could no longer be divided. Democritus called these infinitesimally small pieces of matter atomos, meaning "indivisible." He suggested that atomos were eternal and could not be destroyed. Democritus theorized that atomos were specific to the material that they made up. It is said that another scientist, Leucippus, helped him develop this theory; though, there is speculation on whether that statement is true or not.
Through his observations of morning fog and other weather patterns, Dalton realized that water could exist as a gas that mixed with air and occupied the same space as air. Solids could not occupy the same space as each other; for example, ice could not mix with air. So what could allow water to sometimes behave as a solid and sometimes as a gas? Dalton realized that all matter must be composed of tiny particles.
In 1913, Bohr published a theory about the structure of the atom based on an earlier theory of Rutherford's. Rutherford had shown that the atom consisted of a positively charged nucleus, with negatively charged electrons in orbit around it. Bohr expanded upon this theory by proposing that electrons travel only in certain successively larger orbits. He suggested that the outer orbits could hold more electrons than the inner ones, and that these outer orbits determine the atom's chemical properties.
These men were determined scientists that set out to understand the world better. While one maybe improved on a previous scientists theory, another one may have created his own theory. Also, the scientists different ways of thinking helped them come up with different theories concerning the atom. As a whole, these theories are combined to explain what we know of the atom present day. The earlier scientists figured out the atom logically instead of through physically through experimentation like the later scientists.
Democritus and Leucippus had to have great understanding and insight on the way the world works to be able to come up with such complex theories with no way to be sure that they were right and no proof to prove their thoughts. Technology and the advantage of having previous theories to help them definitely put later scientists at an advantage over the earlier ones. They still had to work hard to find out information about the atoms, but they were able to utilize technology and build on a previous foundation, whereas the previous scientists basically had to start out from scratch by just pondering the ways of the world. It's incredible that they were able to come up with such complex theories just by thinking deeply about something.
The atomic theory is still a theory not only because it has a few mistakes and it is not completely proven, but also because it is not complete and their are things still being discovered about the atom.
It is important that we understand the structure of the atom because everything is made out of atoms; also, by understanding the structure of it, we may be able to better understand it's capabilities, such as the fact that splitting an atom causing a mass explosion. There still may be more that an atom can do that we haven't discovered yet.
www.visionlearning.com
www.lucidcafe.com
www.infoplease.com
Charlotte Quaas
The main characters in the development of the atom were: John Dalton, J.J. Thompson, Ernest Rutherford, Neils Bohr, and Schrodinger. They were all important contrubutors to the atomic structure.
John Dalton proposed the Atomic Theory in 1803 which stated that (1) all matter was composed of small indivisible particles termed atoms, (2) atoms of a given element possess unique characteristics and weight, and (3) three types of atoms exist: simple (elements), compound (simple molecules), and complex (complex molecules).
In 1887 J.J. Thompson discovered the first component part of the atom; the electron. In 1904 he proposed an initial model of an atom which he pictured as a sphere full of an electrically positive substance mixed with negative electrons, like chocolate chip pudding.
Ernest Rutherford discovered the atomic nucleus. His new model of the atom showed that it's positive electric charge and the majority of it's mass were concentrated in a nearly point sized nucleus. The electron in an atom circles the nucleus like the planets orbit the sun, and the attractive electron force plays the role which gravity plays with the planets. Which is where we get the name "atomic planetary model".
In order to take account for atomic stability, in 1913 Niels Bohr created a new model of the atom: "The orbits of the electron cannot be anywhere but quantified; only certain particular orbits are permitted for the electron". It's not until one jumps from one orbit to another that it can emit light.
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Erwin Schrodinger shows us that these electrons don't even move. The waves are stationary. Each time you check where an electron is you will find it in a different place, but that doesn't mean it's moving in between checks. For some energy levels, if you check position enough times you may see an "orbit-like" pattern, but don't be fooled into thinking that electrons are actually moving around in little circles.
These people were different because they had the patience and enjoyment in studying and coming up with theories about things to small for the naked eye to see. Plus these scientists all dared to be different by being smarter than all of the people of the era they lived in.
Some of these scientists grew up with a great education and rich families while others just simply had to come up with the tools they needed to perform their research the hard way; by making them or just using what they had at the time.
The atomic theory is still considered a theory because there are more discoveries made on it and many questions still unanswered. It is still being tested and changed and has no specific definition.
Understanding the atom also helps us understand the world around us since the world is made of atoms. Plus we might need to know about an atom for like a test of something important in class.
History of the Atom
-who were the main characters in the development of the atom
Leucippus, Democritus, Epicurus, John Dalton, J.J. Thompson, Ernst Rutherford...
- Why were they vital to the development of the atom
-Leucippus- started frenzie; wondered when pieces were at their smallest.
-Democritis- student of Leucippus; thought same way; together developed ideas.
-Epicurus- first to teach theory of atoms in 306 B.C.
-Robert Boyle- showed evidence and logic to the theory of an atom.
-John Dalton- solidified the atomic theory.
-J.J. Thompson- experimented with cathode rays and finalized the name of the electron, corpuscles; drew the raisin pudding model of the atom
-Ernst Rutherford- experimented with radiation and updated Thompson's raising pudding model.
-James Chadwick- Proved that neutrons, neutral particles in the nucleus that made up approximately half the mass of an atom, did exist; Summary of Subatomic Particles
-what made them different if anything
They solidified all of their results and most were the first to find what they found.
- Think about your lessons in history and discuss how the time period that they lived in determined the outcome of their discovery/ or how it influenced those individuals to be the names that we know today (aka did it matter where they grew up or if they had money?)
Due to the like of technology way back when, I'm assured that they were limited to what their experiments could provide. Also, most of the world was in poverty and there were only a few select wealthy families, who were the only one's whose voice was heard in society. This affected who's experiments were known.
- Why do we consider the atomic theory still a theory? What are the new developments- would love for you to share new sources here about what you find
Only part of the theory has been proven, but not all. We now know that atoms are not truly indivisible.
source-your notes.
- Why does it matter that we understand the structure of the atom
so we can better understand the structure and use it to our advantage in creating new stuff.
atom
John Dalton, Bohr, and JJ Thomson were the main discoverers of the atom.
Because without them, our chemistry class would be based around earth, wind, water, and fire. Honestly, it would be mostly boring.
They were the ones who dared to be persecuted for being smarter than the general population and they led they way for other discoveries.
the atomic theory is still a theory because we have yet to prove much in the way of the atom. much is still unknown.
quarks were discovered in the 80s if you consider that recent... research is still being done to find that "island of stability"...
Its important because we want it to be. im sure life could continue somewhat normally without knowing everything on the earth...
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