"After matriculation at the Gammelholm Grammar School in 1903, he entered Copenhagen University where he came under the guidance of Professor C. Christiansen, a profoundly original and highly endowed physicist, and took his Master's degree in Physics in 1909 and his Doctor's degree in 1911.
What did Niels Bohr discover that related to the ATOM?
* Bohr's model
* The theory that electrons travel in discrete orbits around the atom's nucleus, with the chemical properties of an element being largely determined by the number of electrons in its outer orbit.
* The idea that an electron could in fact drop from a higher-energy orbit to a lower one, emitting a photon (light quantum) of discrete energy (this became the basis for the quantum theory).
* Much work on the Copenhagen interpretation of quantum mechanics.
* The principle of complementarity: that items could be separately analyzed as having several contradictory properties.
Actually, Niels Bohr didn't do too much with the bomb directly. In the early 1900, he presented the first orbital model for electrons, where electrons in the first, second, etc levels had 2,8,18 etc. electrons. Later on, he did work with uranium processing. There is an interesting story that supposedly happened when the Nazis invaded Norway in 1940. He had one of the largest supplies of heavy water (pure deuterium oxide) in a beer bottle in his refrigerator (talk about security!!). He escaped, grabbing what he thought was the heavy water with him. However, it turned out to be a bottle of beer. Luckily, someone managed to get the heavy water before the Germans could figure out what happened or some soldier drank it down.
What experiments did Niels Bohr do that lead him to create his model of the atom?
Niels Bohr is best known for the investigations of atomic structure and also for work on radiation, which won him the 1922 Nobel Prize for physics. Niels Bohr applies quantum theory to Rutherford's atomic structure by assuming that electrons travel in stationary orbits defined by their angular momentum. This led to the calculation of possible energy levels for these orbits and the postulation that the emission of light occurs when an electron moves into a lower energy orbit. He developed the planetary model theorizing that an atom had electrons orbiting around it. he was correct.
How come Niels Bohr's electron planetary model could not be applied Universely?
Because it was not an accurate representation of an atom. Electrons circling a nucleaus can really be anywhere is space around a nucleus. Based on the energy level of the electron, there are probablity fields that say where it will most likely be, but there is not determining that for sure, it is all probability.
Also, Bohr's model was only 2-dimensional. The real word is 3 dimensional.
According to the model of the atom proposed by Niels Bohr, electrons move around the atom in _____ or _____.?
I think it's:
According to the model of the atom proposed by Niels Bohr, electrons move around the atom in _orbits_ or _shells_.? When one orbit is filled, the electrons start filling the _outer_ orbit ?
What prompted Niels Bohr to say, "Einstein, don't tell God what to do."?
That would be choice (a). Einstein did not accept the Copenhagen Interpretation of quantum mechanics and famously criticized it by saying "God does not play dice", to which Bohr replied with the given quote.
What was proven wrong about the structure of Niels Bohr atom?
The Bohr model only worked for hydrogen and other one-electron species. The Bohr model was a good beginning but it was quickly replaced by a much more complete model utilizing the quantum theory developed by Max Planck. Despite the fact that undereducated science teachers persist is pushing the Bohr model as a viable model of the atom, it lasted for about 8 years following its introduction in 1913.
Of course, many of us still teach the Bohr model as part of the history of chemistry because, while explaining the spectrum of hydrogen, it because an important contributor to the modern quantum mechanical model of the atom.
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"Move around in orbitals"??? An orbital is simply a three dimensional space giving the probability of finding up to a pair of electrons (of opposite spin). The probability densities we call orbitals are the result of calculations using the Schrodinger wave equation.
Why the Atomic modal of Niels Bohr was considered wrong?
Not "considered wrong." Considered the first (and most important) step along the way to a correct understanding of the atom. Remember, Bohr was the first one to apply the use of quantum ideas and Planck's Constant to the atom and in this he was very, very correct.
I recommend you study the life and work of Niels Bohr. His insights and influence are eclipsed by only a few other people and I mean a very few. You could even make a case that "very few" is actually none. And, in addition, he was a wonderful human being, loved by all he met. After all, he was Einstein's best friend!
Who is Niels Bohr and what was happening at the time?
a danish physicist who was considering what an atom was like in the 1920s
discoveries were made that were incompatible with his idea of an atom as a little solar system
beginnings of Quantum mechanics
check any history of science of the 1900s
What are the changes Niels Bohr did on the model of the atom?
I'm fairly certain he introduced the idea of electron levels, and that electrons can hop from one level to another. We just went over this in class, I'll go check my notes. Sit tight. ;-)
"Contributions to physics
* The Bohr model of the atom, the theory that electrons travel in discrete orbits around the atom's nucleus.
* The shell model of the atom, where the chemical properties of an element are determined by the electrons in the outermost orbit.
* The correspondence principle, the basic tool of Old quantum theory.
* The liquid drop model of the atomic nucleus.
* Identified the isotope of uranium that was responsible for slow-neutron fission - 235U.
* Much work on the Copenhagen interpretation of quantum mechanics.
* The principle of complementarity: that items could be separately analyzed as having several contradictory properties."
I listed a link to the Wikipedia page concerning Bohr. You may find it interesting. As always, you can search for what you're looking for on any large search engine. (Yahoo, Google, etc.)
How did niels bohr actually see the emission spectrum for hydrogen?
Bohr didn't do the experiment, but he proposed the theory that explained the wavelengths in the emission spectrum for hydrogen.
The emission spectrum can be measured by heating the gas, passing the emitted light through a prism and projecting the spectrum on a wall. Balmer did this already for visible light in 1885, i.e. long time before Bohr.
What contribution did Niels Bohr make to the structure of the atom?
He created the "planetary model" of an atom - saying that the atomic energy was focused in the center (in the nucleus - rather than throughout the whole atom) and the electrons rotated around it in fixed paths (which was later proven to be incorrect).
Actually Neil Bohr invented quantum physics along with several other physicsts of his day.
His greatest contribution has to be the fact that he never backed down from Einstein's relentless challenges to the validity of quantum physics.
One of the greatest ironies of our times is that even though Einstein was one of the greatest physicists who ever lived, and had contributed more than anyone during his lifetime to human knowledge and understanding of the Universe, he was also one of the greatest obstacles to the development of quantum physics in the early twentith century.
However, it was Neil Bohr who rose to the challenge of defending the nascent sciencific theory at the time. If it hasn't been Neil Bohr, no one would have had the balls to go up against such a legend such as Einstein and made quantum physics widely accepted by physicists then and today.
Neil Bohr was truly responsible for the revolution that made quantum mechanics a part of modern physics.
What principle did Niels Bohr propose to explain the emission lines in the hydrogen atom?
I'm not sure what you are looking for...
The electrons travel in orbits and have discrete quantized momenta, and therefore quantized energies. That is, not every orbit is possible but only certain specific ones, at certain specific distances from the nucleus.
The electrons will not slowly lose energy as they travel, and hence will remain in stable, non-decaying orbits.
The great significance of the model is that it states that the laws of classical mechanics do not apply to the motion of the electron about the nucleus. Bohr proposed that a new kind of mechanics, or quantum mechanics, describes the motion of the electrons around the nucleus. This model of electrons traveling in quantized orbits around the nucleus, however, was replaced with a more accurate model of electron motion about ten years later by the German physicists Erwin Schrödinger and Werner Heisenberg.
Or are you looking for a formula???
When an electron makes a jump from one orbit to another, the energy difference is carried away (or supplied) by a single quantum of light (called a photon) which has an energy equal to the energy difference between the two orbits.
The allowed orbits depend on quantized (discrete) values of orbital angular momentum, L according to the equation
L = n * h = n * h / 2pi
Where n = 1,2,3,… and is called the principal quantum number, and h is Planck's constant.
Point (2) states that the lowest value of n is 1. This corresponds to a smallest possible radius of 0.0529 nm. This is known as the Bohr radius. Once an electron is in this lowest orbit, it can get no closer to the proton.
Hope that's what you were looking for. Good Luck.
Niels Bohr was a Danish physicist who was born in Copenhagen (Denmark). He worked at the University of Copenhagen and later founded the Institute of Theoretical Physics in the city in 1921, becoming its director. During World War II Germany occupied Denmark and Bohr escaped to Sweden in 1943 to avoid being arrested by German police. From Sweden he then moved to London. He worked on the Manhattan Project to build the American nuclear bomb in Los Alamos (New Mexico, USA) and then moved back to Copenhagen after the War to work on peaceful uses of nuclear energy. He died in Copenhagen in 1962.
What was Niels Bohr's apparatus or experimental set up for making his theory?
Basically, this is it -
In atomic physics, the Bohr model depicts the atom as a small, positively charged nucleus surrounded by waves of electrons in orbit — similar in structure to the solar system, but with electrostatic forces providing attraction, rather than gravity, and with waves spread over entire orbits instead of localized planets.
The Bohr model is a primitive model of the hydrogen atom that cannot explain the fine structure of the hydrogen atom nor any of the heavier atoms. As a theory, it can be derived as a first-order approximation of the hydrogen atom in the broader and much more accurate quantum mechanics.
I would say these things (from Wikipedia, look at the part under his pic where it says "known for" and it'll give you a short list). The go to contributions to physics and chemistry and it'll give you pics too.
-The Bohr model of the atom, the theory that electrons travel in discrete orbits around the atom's nucleus.*** Big one if you're in a basic chem class
-The shell model of the atom, where the chemical properties of an element are determined by the electrons in the outermost orbit.
-The correspondence principle, the basic tool of Old quantum theory.
-The liquid drop model of the atomic nucleus.
-Identified the isotope of uranium that was responsible for slow-neutron fission – 235U.
-Much work on the Copenhagen interpretation of quantum mechanics.
-The principle of complementarity: that items could be separately analyzed as having several contradictory properties.
seriously dude, just read the parts of the wiki page that correspond to what you need. it'll take less time then asking all these questions here.
How does an orbital defined by the quantum mechanical model differ from the one described by Niels Bohr?
the electrons dont really travel around anything in any conventional sense
they merely exist near the nucleus. each time you look they will be in a different place. they could be anywhere, but the probability of finding it in a given volume is predictable. so you end up with more of a 'cloud' than an orbit. and the 'clouds' are denser in some places, and empty in others
the picture on here http://en.wikipedia.org/wiki/Atomic_orbital is a good representation of what the 'clouds' 'look' like. some are freaky looking!
QM is also a very accurate model, just fyi
How does Niels Bohr differ from Ernest Rutherford?
This is far too big a question. A term of lectures and a few books would be a good start.
But just to give one start.
Bohr and Rutherford DON'T differ.
Rutherford concluded that the atom had a heavy dense small positive nucleus and was surrounded by light negative charge/charges.
Bohr concluded that the negative charges could be given different amounts of energy but only certain definite amounts were possible. So the electrons were limited to specific orbits.
These two are quite compatible with each other.
How did Niels Bohr resolve the dilemma of electron configuration about the nucleus of the atom?
The Bohr model of atomic structure was developed by Danish physicist and Nobel laureate Niels Bohr (1885–1962). Published in 1913, Bohr's model improved the classical atomic models of physicists J. J. Thomson and Ernest Rutherford by incorporating quantum theory. While working on his doctoral dissertation at Copenhagen University, Bohr studied physicist Max Planck's quantum theory of radiation. After graduation, Bohr worked in England with Thomson and subsequently with Rutherford. During this time Bohr developed his model of atomic structure.
Read more: Bohr Model - Energy, Electrons, Quantum, and Electron - JRank Articles http://science.jrank.org/pages/982/Bohr-Model.html#ixzz1lc1Bk35n
How did Lord Rutherford, Max PLanck, and Niels Bohr contribute towards the atomic theory?
Rutherford theorized about the neutron and found the half life
Bohr created the Bohr model that has electron orbiting the nucleus like the solar system. "The theory that electrons travel in discrete orbits around the atom's nucleus, with the chemical properties of an element being largely determined by the number of electrons in its outer orbit."
Planck- E = hν where h is his constant, V is frequency and E is energy. (Relationship between frequency and energy of light)
Curie i think- she isolated Polonium
Einstein- E=MC^2 (relationship between mass and energy)
What arrangement of electrons did Niels Bohr discover that explained why electrons did not get captured by....?
The electrons have a set amount of energy, arranged into levels of increasing energy the farther they are from the nucleus. So, for example, E=1 is the first energy level where the energy of the electron is what that energy level is too.
Also, as you go out, the energy levels get closer together. So, E3 and E2 are closer together than E1 and E2.
Basically, electrons cannot have an energy lower than the first energy level. It would have to be lower for the electron to get to the nucleus. But it cannot go that low. Bohr discovered that it happened, and I think we're still looking for why it doesn't.
For more: http://en.wikipedia.org/wiki/Bohr_model
Niels Bohr's contribution to the model of the atom?
neils bohr theorized that the orbits of electrons in atoms was quantized.
that is, that the energy levels can only have very specific values. transitions from one orbit to another could thus only occur via the absorption or emission of photons of very specific energies that are specific to the levels of interest and also the atom....
this was a very radical proposal at the time, and was of course completely correct.
Niels Bohr's model of the hydrogen atom is different from the classical physical model. What does the Bohr mod?
it modeled the wavelight nature of electrons.
basically, all matter has a deBroglie wavelength
he "wrapped" around the wavelelength of electrons - based on their velocities and observed only discrrete states were allowed where wavelenghts constructivley interfer - thus exaplained, for the first time the quantized nature of energy states
what was niels bohr contribution to atomic theory?
Neils Bohr postulated based on quantum theory that electrons travel around an atomic nucleus in a stationary orbit. His work also led to the theory of different energy levels in atoms, that is if an electron drops from a higher to a lower orbit, it must release energy.
Bohr was the first person to realize that the sharp lines in the emission and absorption spectrum of hydrogen could be explained by assuming the electrons could only have angular momentum equal to an integral number of the value of Planck's constant. It was the first application of the ideas of the quantum nature of the universe to atoms. The Bohr model was replaced in the mid-1920s by the quantum theories of Schroedinger and Heisenberg. However Niels Bohr was for many years the mentor of the new quantum mechanics. Even the interpretation of quantum mechanics was referred to as the Copenhagen interpretation, named after the place where Bohr lived. For years scientists trekked to Copenhagen to consult with Bohr about the newly developing ideas of the nature of the universe.
What is a slogan representing the success of Niels Bohr?
Atomic leap, perhaps?
Atomic, in this case, could either suggest a small success (in relation to the nature of an atom), or a big one like that of an atomic bomb (Bohr's model was really significant, after all). And leap might relate back to the electrons "leaping" from one energy level to the other.
I don't know, that's my best/lousy shot at it.
I don't really think he himself conducted any experiments, as he was mostly a theoretical physicist, to my knowledge. What he did in his model - which he derived from some basic laws of classical physics and using the tweak of quantization (which is, as an assumption, only conjecture but resulted naturally in later models) - was trying to rationalize experimental results of other, more practically oriented physicists that had measured emission lines of hydrogen. So, other people - Balmer, Paschen, Lyman etc. - measured spectra and Bohr devised a model that was able to do at least some explaining, though from a modern point of view the model makes faulty assumptions.
Niels Bohr postulated the quantum model for single-electron atomic systems. His formula is still taught today since it set scientists on the right track for quantum mechanics. It was weak in that it was only applicable to single-electron systems, but not everything is perfect the first time!
The uniqueness of his model was that it stated electrons don't obey classical Newtonian mechanics, but a new set of mechanics we now call quantum mechanics :)