Questions tagged [atoms]
A nucleus made of protons and neutrons surrounded by a cloud of electrons equal in number to the protons.
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Can particles feel hot to the touch? [closed]
The other day, I got a tiny splash of hot cooking oil on my hand. But I could barely feel it because it was so small.
That made me wonder: how hot would a small collection of atoms need to be for me ...
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When two neutral atoms collide, and one atom ionizes, how does the speed of the ejected electron compare to that of the atoms?
When two neutral atoms collide, and one atom ionizes, how does the speed of the ejected electron compare to that of the atoms?
Context is, I was trying to do the calculations for the velocity of the ...
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How large are atomic positional/angular fluctuations within a molecule?
I have seen videos of thermal fluctuations/oscillations of atoms that have covalent bonds with each other, and they are usually quite dramatic. I'm curious how strong the fluctuations really are of a ...
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What happens after a Photon pass-es through an element without causing any ElectronTransition? e.g. A Cube of Scanadium [closed]
Assuming:-
No ElectronTransition ==> Photon passes through the atom. [right?]
Longer Version In Words:- If a Photon doesn't have enough energy / has more energy than to trigger a ...
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Hydrogen atom in a very strong magnetic field
An atom of hydrogen is placed in a very strong magnetic field. The magnetic moment of the orbit of the electron may either align with the external field or may oppose it. What will happen with the ...
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Value of permittivity inside an atom
As we know, the permittivity of free space physically measures how dense an electric field can form in response to electric charges in free space. I have the following 2 questions:
What will be the ...
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Why don't the electron and proton get attracted to each other? [duplicate]
The electron and proton have opposite charges, yet they somehow don't get attracted to each other and stay stable. By attraction, here I mean colliding into one another like magnets with opposite ...
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Question about coherent population trapping
In coherent population trapping, if we denote the ground states in a $\Lambda$-like system as $|0\rangle$ and $|1 \rangle$ and the excited state $|2 \rangle$, there is a linear combination $|d \...
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Is there a momentum representation of the atomic stationary states?
In standard quantum mechanics, the atomic orbitals are represented by the following wave functions (where $u = 2 \mathrm{Z} r / n a$):
$$\tag{1}
\psi_{n l m}(r, \theta, \varphi) = \phi_{n l}(r) \, Y_{...
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Positronium radius more than expected
I am trying to derive the basic properties of positronium. Usually it is stated that we can just set reduced mass of hydrogen atom as $\dfrac{1}{2}m_e$ and obtain:
\begin{equation}
r_n=\dfrac{8\pi\...
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How do electrons absorb photons?
I understand that atom-bound electrons can absorb photons (explanation for why they are typically atom-bound). However, what is the particular mechanism for this occurring? I am familiar with the idea ...
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What is the relationship between the energy absorbed and reemitted by an atom?
What is the relationship between the energy absorbed and emitted by an atom with the model of Lorentz?
In the Lorentz model of an atom, we have that, using the effective cross-sections we might get ...
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Electrons and atoms
Electrons do not follow fixed orbits around an atom's nucleus but exist within "clouds of probability" (orbitals), where there is a high chance of finding them. As one extends the search for ...
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Complete absortion of a photon by an atom (from the perspective of conservation laws)
It is very simple to show that an isolated charged particle cannot completely absorb a photon, since that would contradict the conservation of linear momentum or energy: consider a system where the ...
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How Are Discrete Energy Levels Identified in Metals and Liquids?
The NIST atomic spectra database has atomic energy levels well documented. I understand that discrete energy levels in gases can be identified using emission and absorption spectroscopy, due to the ...
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