# Tagged Questions

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

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### Does Rydberg's formula work for different orbitals?

Rydberg's formula is given as $\frac { 1 }{ \lambda } =R\left( \frac { 1 }{ { { n }_{ 1 }^{ 2 } } } -\frac { 1 }{ { { n }_{ 2 }^{ 2 } } } \right)$ where ${ n }_{ 2 }$ and ${ n }_{ 1 }$ are the ...
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### In Rayleigh scattering, does a light wave cause the electrons (themselves), in a particle, to move at the same frequency as the incoming light?

The excerpt below, about Rayleigh scattering, is taken from the following page: https://en.m.wikipedia.org/wiki/Rayleigh_scattering Rayleigh scattering results from the electric polarizability of ...
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### How many atoms do we need to store a bit?

And which kind of storage (HDD, flash, blue-ray, etc) has the most efficient atoms/bit ratio?
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### Number of photoelectrons vs Frequency

This is the graph plotted between photocurrent (proportional to number of photoelectrons) and potential applied with different frequencies. As it can be seen, the number of photoelectrons released ...
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### How are anti-matter atoms created?

What is the reaction, or reactions that make anti-matter? I don't understand how anti-matter is created by CERN if interaction with normal matter causes annihilation.
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### Is there any antimatter that exists as atoms?

I recently read a few things that implied that there is antimatter that we know of (have created?) that exists as atoms - which I guess means positrons and antiprotons bound together, at least. Is ...
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### Why don't electrons collide among themselves

The Heisenberg principle states that we cannot ascertain simultaneously the position or momentum of any small particle. However slight, is there a chance that 2 or more electrons from the same or ...
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### vibrational motion in gases

In a debate, I argued that vibrational atomic movement as cause of internal energy is prominent in solids (due to their crystal structure) and it is not prominent in gases. I think this also applies ...
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### Can electrons within a positive ion absorb and reflect light?

I understand that in a crystalline metallic structure, such as one making up a bar of gold, there are one, or more, valance electrons of each atom that have left their outer shell (became free ...
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### Element 137 - Theoretical limit [duplicate]

I've seen a few sources that mention the speed of an electron in a hydrogen atom is 1/137 the speed of light. This article also mentions what looks like a correlation between atomic number and the ...
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### 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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### 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 ...
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### Atoms, Gravity and Electrostatic Charge [closed]

How close do 2 atoms of any type the have can be together before gravity with an electrostatic charge that repulses?
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### Does an electron's energy decrease while performing its motion? [duplicate]

While revolving around the nucleus if the electron's energy decreases then will it hit the nucleus and if it does what will happen?
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### What is meant by an excited atom?

I want to know how an atom is when it is excited. If an atom, due to collision of another fast moving atom, becomes fast moving as well, is that also an "excited state"?
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### Earnshaw's Theorem and Plum Pudding

I'm trying to understand what Thompson's motivation for his Plum-pudding model was. He chose the nucleus to be a sphere of uniform charge because it was mathematically nice, and chose the charge to be ...
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### How does conduction happen?

I'd like to ask you how does conduction happen ? I mean, the atoms vibrating more hits the less vibrating atoms and gives energy. But how is that energy transferred ? For atoms to collide they must be ...
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### Can atoms lose electrons by themselves?

I know atoms lose or gain electrons through ionic bonding but when they are by themselves do they lose electrons? I read in a book on metallic bonding which involves free electrons(the lost ones) and ...
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### The atomic mass of an isotope from atomic weight

I'm reading for an entrance exam and have a practice question about the atomic mass of an isotope that I have to figure out. I am given the atomic weight of the element. How can I calculate the ...
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### Is it possible to view an atom? [duplicate]

Is it possible to view an atom? What would it look like? Would it resemble a traditional atomic diagram?
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### Why doesn't silicon emit light? [closed]

Why doesn't silicon re-emit light when light falls on it? Or if it emits light then why we can't see it?Hence it has valence electrons.
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### Gasses and Gravity

I have two questions. First question. When gas is placed inside a container it fills the container evenly with constant pressure. If the container size varies the gas expands or is compressed but the ...
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### Why insulators do not conduct electicity when they are negatively charged?

The following excerpt is from Young and Freedman 13th edition: Most metals are good conductors, while most nonmetals are insulators. Within a solid metal such as copper, one or more outer ...
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### Are atoms elementary? [closed]

I'm reading wikipedia about Real neutral particle. I know, there are many different particles discovered in the background of atom, which was ( Neutrons + Protons + Electrons ) before. For example, ...
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### What does an orbital mean in atoms with multiple electrons? What do the orbitals of Helium look like?

I am wondering about this. It is a familiar sight, the orbital diagrams for the hydrogen atom, depictions of which are abundant and so are not in need of reproduction here. However, what about the "...
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### Does the attached figure show how particles produce wave?

I have always been trying to understand and visualize what wave is and how it's been produced. I guess what ordinary people know about wave is just a particle moving up and down but last week I came ...
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### What is the reason behind the very high value of nuclear density? [closed]

I know how to arrive at the formula but I want to know it's such a huge number almost 2 X 1017 kg m-3, which is a huge number, all the more surprising to me is that it's a constant! Each and every ...
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### Can you see Bose-Einstein condensates with the naked eye?

In this article it is said that "A BEC is a group of a few million atoms that merge to make a single matter-wave about a millimeter or so across." Does this mean that when they make a matter wave ...
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### Does the proton wobble due to the electron's orbit in a Hydrogen atom?

In a hydrogen atom the nucleus only has one proton and no neutrons so the electron to nucleus radio is higher for hydrogen than that for any other atom. Does the orbiting electron induce a wobble on ...
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### How does heat damage the body? [closed]

Let's take an example : If I put my hand in cold water (let's say 20°C), it doesn't hurt, and it doesn't burn. But if I put my hand in hot water (let's say 90°C), it hurts and my hand can get burnt. ...
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### What causes the blur when my fingers are almost touching? [duplicate]

I can see this with my bare eyes
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### What is the largest distance for which the influence of the electric field of a single electron was measured?

I suppose that Rydberg atoms are the best way to find by experiments the largest distance of influence of the electric field of a single electron in a electric dipole. Furthermore how the electrical ...
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### do gravity shows its effect in atomic level? [duplicate]

how much of a effect do gravity shown in atomic level. how significant or negligible is it. i am guessing the effect is small because the mass of nucleus and electron is small. But the distance ...
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### Can you breakdown an atom?

Protons, neutrons, and electrons make up the atom, but I've heard that you can't breakdown an atom. How do we know that the electrons, protons, and neutrons make up the atom without being able to ...
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### The force applied by two charges on each other when there is another charge nearby them

QUESTION 1 Let me give two simple scene of charged particles to make you understand my question. There is a fixed positive charged particle in the center. Scenerio 1 : A fixed negative charged ...
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### How is magnetic field created in an atom according to quantum model

How is magnetic field created in an atom according to quantum model? I mean, we are taught about the magnetic field by bohr's model which assumes that electron revolves around the nucleus in a ...
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### Splitting molecule

The photon reacts with the binding electrons orbiting the two atoms. The photons have the 'correct' wavelength for Bond Dissociation Energy (BDE). 'Splitting' the molecule involves applying the ...
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### How to determine what an object is composed of?

Heads up: This question has never been asked (here) before the way I will ask it here, so let's shed some light on it a bit. Prelude and anecdote(can be skipped): The other day I was walking home, ...
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### Can we touch the atoms? [duplicate]

This question is basically a spin off from my friend's question - "What are we basically seeing? Is it the atom or the nucleus?" (He had referred to the huge amount of empty space inside the atoms). I ...
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### When light is reflected, if some of the light is absorbed in the particle, does it change the particle?

Which color/frequency of the light is absorbed and which part is reflected? How is it determined which part will be absorbed? Does that depend on the particle? N.B: When I say particle, please keep ...
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### Deexcitation times for ytterbium

I need to find the deexcitation times for the transitions found in Figure 1 of Nature Phys. 8, 649 (2012), arXiv:1206.4507. That is, what is the deexcitation time for the following transitions:  ^...
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### Why do electrons have to fall on the nucleus in the Rutherford atomic model?

As I read on Wikipedia, the Rutherford atomic model is not correct according to classical electrodynamics, as it states that electron must radiate electromagnetic waves, lose energy and fall onto the ...
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### Struggling with a conversion. Showing number of atoms per cubic meter using pressure in Torr

I have been trying to show that the following is true: N = 9.65 x 10^24 x (P/T) Where N is the number of atoms per cubic meter of an ideal gas at pressure P (in Torr) and temperature T (in Kelvin). ...
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### How much of the Solar convection zone is completely ionized?

I was reading about the energy transportation in stars here, and I found this: "The outer portion of solar mass stars is cool enough that hydrogen is neutral and thus opaque to ultraviolet photons, so ...
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### Difference between spin-orbit coupling and LS coupling (Russell-Saunders)

I'm having some trouble understand what the difference is between these two. It seems as though there are kind of the same, but that spin-orbit coupling reduces to LS coupling under certain ...
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### How does positronium work?

I've heard that in positronium, electrons and positrons orbit each other before annihilating one another shortly after. However, I thought that electrons never orbit anything, but instead have a ...
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### Can the atomic vibration of molten liquids be decomposed into a superposition of a series of normal modes?

From what I've learned, molten liquids have short-range periodicity (short-range doesn't just apply to the amorphous solid state/glassy state). So does this mean that, along with amorphous solids, the ...
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### Atomic natural line width

In laser cooling, with a model of a 2-level atomic system, spontaneous emission is stated to be dependent on the "natural line width" of the excited state of the atom. This width is defined as the ...