A nucleus made of protons and neutrons surrounded by a cloud of electrons equal in number to the protons.

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1answer
67 views

J.J. Thomson's cathode ray tube: Why does the magnetic field bend the cathode ray downward?

The cathode ray is bent upward toward the plate by electric field and downward by the magnetic field. The first part isn't what I am confused about. However, the second part is. How did the ...
4
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1answer
502 views

What are independent parameters in Hellmann–Feynman theorem?

A typical example in textbooks about the application of Hellmann–Feynman theorem is calculating $\left\langle\frac{1}{r^2}\right\rangle$ in hydrogen-like atoms. Wikipedia has a nice demonstration of ...
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3answers
62 views

Do electrons get accelerated or decelerated by the atoms of the anode during X-rays production?

The electrons striking the anode get deflected by the heavy nucleus. Though the speed may or may not change, the direction of motion changes which leads to acceleration. The charged particles emit ...
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8answers
484 views

Can I throw a stone through my window without breaking the glass?

As far as I know, most of an atom is vacuum. Therefore, in theory, would it be possible for me to throw a tiny stone through my window without breaking it because no matter actually collides?
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1answer
77 views

Is charge transfer from A to B positive or negative?

I see this term pop up a lot -- for instance "charge is transferred from atom A to atom B", but it's never specified whether they're talking about positive or negative charge. I know electrical ...
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0answers
21 views

Photon absorption by a hydrogen atom : [duplicate]

How does the photon absorption takes place in a hydrogen? The classical mechanics shows the absorption of photonic energy resulting in the excitation of atom. Intuitively, a photon with frequency ...
1
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0answers
143 views

Total angular momentum in multielectron atoms

I have some confusion about orbitals in multielectron atoms. Let's say we consider an atom (Lithium, for example, $1s^2\, 2p^1$) and that the state of the last electron is [n=2, l=1, ml=0, s=1/2, ...
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5answers
5k views

Which experiments prove atomic theory?

Which experiments prove atomic theory? Sub-atomic theories: atoms have: nuclei; electrons; protons; and neutrons. That the number of electrons atoms have determines their relationship with other ...
32
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4answers
4k views

Are atoms unique?

Do atoms have any uniquely identifying characteristic besides their history? For example, if we had detailed information about a specific carbon atom from one of Planck's fingerprints, and could ...
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0answers
122 views

How to calculate the $g$ degeneracy factor for alkali metals and their singly ionized species?

The Saha ionization equation is $$\frac{n(X_{i+1})}{n(X_{i})} = \frac{(2\pi m k T)^{1.5}}{n_e h^3}\frac{2g_{i+1}}{g_{i}}e^{-\chi/kT}$$ where $\chi$ is the energy difference between the two ...
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3answers
141 views

The atom, solid or liquid? [closed]

Now I know what you may be thinking, "buddy, do you realize that the quality of solid or liquid is Made by the sum total of atoms in a thing therefore an atom can't be a solid or liquid??" This, good ...
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11answers
3k views

Where did Schrödinger solve the radiating problem of Bohr's model?

One of the problems with Bohr's theory to describe the hydrogen atom, was that the electron orbiting around the nucleus has an acceleration. Therefore it radiates and loses energy, until it would ...
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2answers
727 views

The distance between touching objects

What is the distance between, say, a cup of coffee and the table it rests on? What is the distance between two touching hands?
108
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3answers
9k views

How does a knife cut things at the atomic level?

As the title says. It is common sense that sharp things cut, but how do they work at the atomical level?
4
votes
1answer
89 views

How do mirrors look & behave atomically?

I was observing mirrors recently and I was thinking about how an mirror would look atomically. I was always used to looking at atoms as being colored that said, I was always concerned at how they ...
4
votes
4answers
584 views

Why does optical pumping of Rubidium require presence of magnetic field?

The optical pumping experiment of Rubidium requires the presence of magnetic field, but I don't understand why. The basic principle of pumping is that the selection rule forbids transition from ...
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3answers
13k views
3
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1answer
154 views

Why is cesium used to measure time in atomic clocks?

Seconds are measured by the frequency emission of cesium. Why is a frequency from the emission spectrum of cesium used as the standard in defining a second? Why particularly cesium?
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2answers
670 views

Miniature Neutron Stars?

Is the nucleus of a carbon atom, for example, as dense as a neutron star? I read that neuton stars also contain protons. Thinking more broadly, are we surrounded by quadrillion of quadrillions of ...
46
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8answers
18k views

Why don't electrons crash into the nuclei they “orbit”?

I'm having trouble understanding the simple "planetary" model of the atom that I'm being taught in my basic chemistry course. In particular, I can't see how a negatively charged electron can stay ...
29
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4answers
4k views

Has gravity ever been experimentally measured between two atoms?

Has there been any experiments, or are there any references, demonstrating gravity between atoms? If so, what are the key experiments/papers? Or if not, what is the smallest thing that has actually ...
2
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1answer
164 views

Question about atom subshells

So my teacher told me that EACH shell contains 5 subshells (s, p, d, f, g) but what I don't understand is this The 1st shell has only 1 subshell (and not 5 like he said) and the number of ...
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0answers
30 views

What happens when electromagnetically shunken coin is heated

The question is simple: What happens to coin/object that was electromagnetically shrunken by a coin crusher device is then heated until it (I asume) melts? Do I have misconception or not just ...
4
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2answers
591 views

Neil deGrasse Tyson says that electrons “teleport” between energy levels?

This page: https://blog.afach.de/?p=62 Discusses the error Neil deGrasse Tyson made when talking about electronic transitions (video included there). Tyson clearly said in his Cosmos series that ...
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1answer
74 views

Formation of atoms question

Could you please, explain to me the logic of the folllowing process as you would do to your 8 y/o sister: Ubiquitousness and stability of atoms relies on their binding energy, which means that ...
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4answers
512 views

Quantum mechanics threshold

First of all I beg your forgiveness as I am not a physicist and the question I am going to ask may sound silly. I am aware that beyond a certain threshold in the hierarchy of building blocks of ...
3
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2answers
74 views

Do atoms produce synchrotron radiation?

Since synchrotron radiation is created when charged particles are radially accelerated and electrons are definitely orbiting a nucleus (assuming a Bohr model), electron should then logically emit ...
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0answers
35 views

Books on collision probability and collision processes

Are there any books specifically on collision processes between atoms and molecules and collision probability? I would like to get an overview of the factors that determine collision probability ...
2
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3answers
161 views

Can lightly-ionized atoms be accelerated to relativistic speeds with current technology?

I know there're lots of various particle accelerators, which can accelerate particles to TeV's of energy, but it seems they all work on electrons or nuclei or other elementary of tightly-bound ...
2
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0answers
112 views

Is the translational information all that matters, or do we need to take into account internal states?

For anyone in this community that's familiar with quantum teleportation, I need desperate help. I am currently working on my senior thesis and my goal is to teleport a molecule. Background: So in ...
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2answers
158 views

What is Quantum jump of an electron?

Can any one define quantum jump 9 quantities jump of an electron ? I know it it is a silly question but can anyone please explain me in detail.I am a learning about the structure of atom and I want ...
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4answers
3k views

How can one describe electron motion around hydrogen atom?

I remember from introductory Quantum Mechanics, that hydrogen atom is one of those systems that we can solve without too much ( embarrassing ) approximations. After a number of postulates, QM ...
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2answers
129 views

My book uses helium weight in reaction formula instead of weight alpha particle?

I'm suppose to write out reactions where atoms send out alpha radiation and decay. The book uses the 4-2 H, 4 as nucleon number and 2 as proton number, but isn't that wrong? The mass of helium is ...
0
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2answers
85 views

Can a hydrogen atom sit still?

Can we take a single lone hydrogen atom (proton and electron?) and set it in one place and observe it staying there? How about just a proton? A neutron? How about just an electron?
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2answers
137 views

Mathematical description of electron configuration

Does there exist a mathematical model for determining the electron configuration of an atom? I mean the theory which would generalize the notion behind the informal elements of the Aufbau principle.
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3answers
72 views

Demonstration that vibrating basic particles constitute non-vibrating individuals

I am a dilettante in physics; I ask for pardon for my confusion-causing (if any) terminology usage, and also for my imprecise choice of question tags. I know that basic particles of any individual ...
3
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1answer
113 views

Measuring Atomic Radius of a Noble Gas

How exactly can you measure the atomic radius of a noble gas such as Neon or Helium accurately? Would liquefaction help? I also heard that the aforementioned gases are the only common elements which ...
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vote
1answer
202 views

Hydrogen ionization energy [closed]

Proton and electron have a distance equal to the Bohr radius apart in the hydrogen atom. Knowing this, what's the ionization energy of the atom? So we know $U = -kq^2/a_B$, but this is potential ...
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0answers
58 views

Formation of atoms [closed]

If a Proton goes toward an Electron with a trajectory that forms a circular motion, these particles will form an atom ?
0
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1answer
79 views

Can an object be deconstructed on an atomic Level?

Can a machine deconstruct objects on an atomic level. But is that possible? Not the machine per say but the simple (not that simple) act of what it does. Ex.Taking a broken computer and separating the ...
5
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3answers
370 views

What makes materials hard and strong?

This is something I have wondered for a long time. Why are some materials like steel, diamond, and even light materials like graphene stronger than others? Is it due to the strength of the ...
0
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1answer
138 views

What is a real world application of Madam Curie's life work?

As in the title. I know she was working with radioactive atoms and she made huge progress in the field of physics. But where would you find the application of her discoveries in our world? Is it just ...
6
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2answers
103 views

Why do $\beta$ particles not get attracted to the nucleus?

I currently have a very limited knowledge of how radiation works etc, but while sat in class the other day, one question occurred to me that even my teacher could not answer. We have been learning ...
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0answers
189 views

Space between particles [duplicate]

I am a high school student, and I am just wondering what is the space between each particle, like what is the gap around each atom? I have found no text book cover this topic. Is it a vacuum?
3
votes
3answers
568 views

Can I move the atom nucleus only?

I was wondering if it is possible to move the atom nucleus and leave behind the electrons? I can imagine that the electrons will follow the nucleus. But what if the speed of the nucleus is almost the ...
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votes
1answer
1k views

Why aren't atoms affected by gravity, but molecules are?

I read this book here: http://tiny.cc/Gravity-Atom-Myth It claims that while gravity does affect individual atoms, it's not quantified like molecular mass due to lack of binding proteins which render ...
3
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2answers
835 views

Atomic nucleus consisting of only neutrons?

Is it true that the nucleus of all atoms (including radioactive isotopes) contain at least one proton? Is there an atomic nucleus consisting entirely of neutrons? (Let's exclude neutron stars for the ...
4
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5answers
3k views

How can the nucleus of an atom be in an excited state?

An example of the nucleus of an atom being in an excited state is the Hoyle State, which was a theory devised by the Astronomer Fred Hoyle to help describe the vast quantities of carbon-12 present in ...
3
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3answers
55 views

Real silicon atom structure?

Text books say that a pure silicon atom has four electrons in its outermost orbit. How do the scientists know it has four electrons?
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2answers
55 views

Does the doppler shift have any effect on the energy that the atom absorbs?

Does an atom moving towards the light that is falling on it, absorb more energy than when it is stationary? The atom should a see blue shift due to Doppler effect so the atom will see a light of ...