Questions tagged [electrons]
Electrons are subatomic particles with the symbol e−. They have a negative electric charge (-1 elementary charge. )
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When we write nd* in electron configurations, does that have anything to do with antibonding orbitals? (n = electron layer) [closed]
The title says it all. For example, when we make a sigma* or pi* antibonding orbital, does that correlate to excited electrons, especially in transition metals? Or is that a different topic? Thanks
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How is MnS + 2HCl -> MnCl2 + H2S a redox reaction, in terms of electron transfer?
$$\ce{MnS + 2HCl -> MnCl2 + H2S}$$
If oxidation and reduction is taken to be the loss of hydrogen and the gain of hydrogen respectively, then I can see how the aforementioned reaction is redox — $\...
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how does an electron from a Zn solid overcome all barrier and make it all the way to Cu2+ solution
I am trying to imagine the journey of the electron:
When electrons are in a Zn metal bar, all electrons have lower
potential energy compared to 0 ev potential. In order for an electron to
escape from ...
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AlCl3 and water
While reading Clayden's (et al) Organic Chemistry I stumbled upon a reaction on page 120 that I just fail to wrap my brain around. It describes a reaction of AlCl3 with water and states that, quote, &...
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When an aromatic compound has an allyloxy group (R = OCH2CHCH2) as substituent, is this group electron-donating or electron-withdrawing? [closed]
I am dealing with 5,10,15,20-tetra(allyloxy-phenyl)porphyrin and I want to understand the effect the allyloxy groups have on the porphyrin nucleus.
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How do you draw the pi MO diagram for the acetate ion CH3COO-
How do you draw the pi MO diagram for the acetate ion CH3COO- ? I get stuck with the number of electrons on the 2p orbital of Oxygen atom. My teacher said 1 oxygen has 1e, the other has 2e. But ...
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How do we write spin multiplicity for Mn(2+), Mn(7+)?
Mn has atomic number = 25
Since it is an exception to electronic configuration , unlike having = $\mathrm{3d^7}$ , it has electronic configuration = $\mathrm{3d^5,4s^2}$.
Formula for spin multiplicity ...
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What kind of electronic configurations are possible?
Let us take $d^6$ orbital as an example:
A) ↑ | ↑ | ↑ ↓ | ↑ | ↑ |
Now , this one 1 way. My Q is that how is it possible that in the 3rd box , we have a paired electron but not in the 1st one. Like it ...
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What will the correct value of spin quantum number for last electron of Na+ ion?
Electronic configuration of $Na^+$ ion is $1s^2,2s^2,2p^6,3s^0$.
I have noticed usually , we take spin quantum number as +1/2 first & then -1/2.
So , like for the above Q:It is for first 3e=+1/2 &...
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Why is the momentum operator imaginary?
I'm a beginner in quantum mechanics, and I'm pretty much confused with the momentum of electron in hydrogen atom.
The wave function of the electron in 1s orbital of hydrogen atom is $\Psi_{1s} = \frac{...
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Why is the distribution of electrons of calcium in K,L,M,N shells 2,8,8,2 instead of 2,8,9,1?
I'm a beginner to this topic, so this would likely sound dumb. As far as I know, when distributing electrons in energy shells, the last energy shell can't have more than 8 electrons. So for calcium, ...
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1answer
107 views
Evidence that electrons don't exist between orbitals? [closed]
I don't understand the logical jump that was made early on in the atomic age, to conclude that electrons jump in and out of existence when moving between orbitals? Similarly, why do electrons need to ...
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True or false: "A used AA battery contains fewer moles of electrons than a new AA battery."
I recently took a Gen. Chem. 2 exam that contained this question. I answered false, but my professor said the answer is true. My reasoning was that any electrons that leave the anode end up at the ...
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What happens inside the orbital when energy provided to electron is not sufficient for it to change orbitals? [closed]
While studying the chapter called Atomic Structure, we were introduced with Bohr's model of an Atom. Even though not all of his postulates were right, I believe some were. A doubt arose in the ...
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How to Combine an Emission spectrum into a colour? [closed]
I am trying to wrap my head around the flame test, and for the most part, it is making sense. My question is their a way to figure out the colour of a flame of an unknown element given the emission ...
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Is there a molecule which has only lone pair electrons? [closed]
Lone pair electrons are "valence electrons that are not shared with another atom in a covalent bond" (Wikipedia).
Is there a molecule which has only lone pair electrons?
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Shielding effect is not constant across a period [closed]
Shielding effect stays constant across a period because number of inner electrons stays the same.
Well, that's not true.
It only works for the period =1,2,3
but in period 4, the number of inner ...
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How to know the number of valence electrons of f-block elements? [closed]
I kinda know how to get the valence electrons for s/p/d- blocks but i don't know about the f-block.
Wikipedia says that valence electrons for f-block is ns + (n-1)d + (n-2)f, so is it true? If so can ...
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Linearity of membrane resistance and contact resistance overvoltages in proton-exchange-membrane-water-elektrolyzer-cells (PEM-WE)
I am questioning why the cell component's resistance to the electrons (contact resistance) and protons (membrane resistance) flow follow the ohmic law. This assumption is made in recent papers on PEM-...
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Why electron configuration of thulium is $[\ce{Xe}]~\mathrm{(6s)^2(4f)^{13}}$ instead of$[\ce{Xe}]~\mathrm{(6s)^1(4f)^{14}}$?
We know that half-filled or full filled orbitals are more stable. That's why the ground state electron configuration of gadolinium is $[\ce{Xe}]~\mathrm{(6s)^2(4f)^7(5d)^1}$ rather than$[\ce{Xe}]~\...
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What does valence electron mean (in the context of spdf orbitals)?
For a little bit of context, my background is in physics and my understanding of chemistry doesn't go past, say, middle school level. Recently, I decided to self-study chemistry and picked up "...
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Can use lead(II) oxide instead of lead(IV) oxide in car battery?
Question: If the discharge input equation $\ce{PbO2}$ is replaced by $\ce{PbO}$, will the battery still work? I think the product will not be water anymore but hydrogen gas. I am asking this question ...
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Which atom is the smallest atom?
Is hydrogen or helium the smallest atom? My teacher said that the smallest atom is the helium atom, but I think that the smallest atom is the hydrogen atom. It has a single electron and a single ...
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1answer
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Hydrated electrons produced by radiation vs electrons from electrostatic charge: are they equally reactive?
One of the species generated in water or aqueous solutions by the ionizing radiations are free electrons that quickly become "hydrated" or "aqueous electrons" (see for example this ...
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1answer
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How does high voltage on the electrodes ionize a gas?
I was studying cathode ray experiment and there the electrons were obtained by ionisation of the gas inthe tube by the high voltage on the electrodes. So how does this happen?
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What would happen if electrons were spin-1?
We were speaking about this in class, but I can't understand it quite well. What would happen if (hypothetically of course) the allowed $m_s$ values were $-1$, $0$ and $1$? What impact does this have ...
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How big a role does electron repulsion play in regard to the bond length of a covalent bond? [duplicate]
In a covalent bond, there are several forces acting together to determine the bond length.
Electron-electron repulsion increases the bond length.
Proton-proton repulsion increases the bond length.
...
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1answer
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Quantifying location and volume of "lone pairs" for VSEPR
Of course molecular shape and the VSEPR model come up frequently.
As discussed previously in a valence bond picture like VSEPR, the lone pair electrons are closer to the atom than bonding pairs, and &...
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How do dielectric molecules in a liquid phase align when polarized?
As seen in the diagram, when a dielectric material becomes electrically polarized, the molecules align themselves in a manner where the respective charges are parallel to each other horizontally.
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When was the mass of hydrogen known?
During Robert Milikan's time, he uses the charge-to-mass ratio from J.J. Thomson's research of the electron (which is $1.759\cdot10^{11}\ \mathrm{C/kg}$) to calculate the mass of electron.
Did he know ...
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Can a metal be forced to form an anion theoretically? [duplicate]
I know that metals have the capability to lose electrons and form cations, but is it also theoretically possible to supply an electron to a metal so that it forms an anion?
If so, has it ever been ...
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Order of Shielding Effect for orbitals
From what I know Shielding effect is the ability of inner electrons to repel outer electrons and reduce the Nuclear charge felt by the outer electrons and this is caused by electron-electron repulsion....
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How can a hydrogen atom ever emit an X-ray photon?
From Scientific American, February 2014:
The Proton Radius Puzzle:
...we had to tune the laser so that it came in with exactly the right amount of energy. The atom would make the jump to the higher ...
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1answer
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What is the average distance between electron 'shells' in an atom? Or between the innermost shell and the nucleus? [closed]
Somehow, I've never come across any mention of the actual, physical distances between, say the 1s and 2s shells in an atom, whether large or small....
I know that p, d and f (and g?) shells are oddly ...
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Why is the bond angle of sulphur difluoride greater than that of hydrogen sulphide?
Why is the bond angle of $\ce{SF_2 (98.05^\circ) > SH_2 (92.11^\circ)}$?
Isn't this contradicting Bent's rule or otherwise electron repulsion rule ? Fluorine is more electronegative and hence it ...
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What would happen if the alpha particles directly hit the electrons in the gold foil in Rutherford's experiment? [closed]
What would happen if the alpha particles directly hit the electrons in the gold foil in Rutherford's experiment?
Would it get ionized or is there no probability of such a thing happening ?
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Thickness of proton exchange membrane (Nafion)?
I am looking into using a proton exchange membrane for a bio-energy cell experiment. Previous scholars have been using Nafion as a PEM to place between the anode and cathode (air-cathode). the ...
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2answers
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What does Bohr's model predict if the mass of an electron becomes 10 times its actual mass? [closed]
If the mass of an electron becomes 10 times its actual mass, which of the following statements is correct regarding Bohr's model:
Velocity of electron increases by 10 times.
Orbit radius decreases by ...
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1answer
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How are Quantum Dot molecules formed and what properties do they hold apart differently from singular quantum dots? [closed]
I am trying to understand the science and phenomena behind the function and operation of quantum dot molecules, but the only articles I run into talk about the synthesis of them. Could this be ...
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Is the spin of the transferred 4s electron always opposite to the spin of 3d electron in chromium?
I am studying atomic structure and found out that Chromium has an exception in electronic configuration. One electron from 4s jumps to 3d to achieve stability.
let's say the spin of transferred ...
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2answers
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How to find the angle of emission of an X-ray during impact of accelerated cathode rays?
X rays are produced when accelerated cathode rays strike a metal target or a metal anode.
How can we find the angle at which the X-ray is emitted from the metal anode or the target when the cathode ...
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Lone pairs of electrons and covalent bonding [closed]
Every time I saw a covalent bond structure, I notice that there are always lone pairs or no electrons left in the outer shell of the atoms. Is it compulsory for covalent bonds to have lone pairs or no ...
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Excitation of electron in Niels Bohr's atomic model
Professor taught us that an electron gains or looses only those energies which are equal to difference in two energy levels. That is $E_1 + \Delta E = E_2$ or $E_1 + \Delta E = E_3.$
What if we give, ...
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Why can't the energy of an electron exceed 0 eV?
Today we were learning about atomic structure, our teacher introduced the mathematics of the 'Niels Bohr Model of Atom', and calculated the value of total energy $\frac{-13.6z^2}{n^2} \pu{eV}$. He ...
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1answer
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Why does STED microscopy cause photodamage?
STED (stimulated emission depletion) microscopy is a technique which enables sub-diffraction limit of light imaging.
The depletion laser is at 775nm, and about 500 mW, concentrated for a short ...
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Do Hartree-Fock (or other model Hamiltonian) electron densities fullfill the Kato theorem?
I have done Hartree-Fock calculations on a single He atom and now I tried to check numerically if the electron density fulfills the Kato theorem. It apparently doesn't. Instead I obtain a cusp ...
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Does a change in oxidation number in a redox reaction mean that an actual electron transfer occured?
Oxidation numbers are fictitious charges that pretend the entire molecule is an ion i.e. it artificially localizes electrons onto atoms within a single molecule. In a redox reaction, we find that an ...
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1answer
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What does "spin degeneracy" mean in this context?
I am currently studying Diode Lasers and Photonic Integrated Circuits, second edition, by Coldren, Corzine, and Masanovic. In chapter 1.2 ENERGY LEVELS AND BANDS IN SOLIDS, the authors say the ...
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Maximum number of Spectral Lines "A better quantum model shows that there will be n^2 transitions"?
I was parsing the following post What is the maximum number of emission lines when the excited electron of a H atom in n = 6 drops to ground state? and came across with the reply from @porphyrin.
cite ...
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If electrons absorb photons to reach higher energy levels in Bohr's atom, why do they have lesser kinetic energy?
In Bohr's atomic model, an electron can jump to a higher energy level by absorbing a photon with energy equal to the difference in energy between 2 energy levels. This should mean that the electron ...
