Questions tagged [electrons]
Electrons are subatomic particles with the symbol e−. They have a negative electric charge (-1 elementary charge. )
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Expanding the octet?
I recently just learnt about this concept of expanding the octet where an atom can exist stably within a compound with more than 8 electrons or less than 8 electrons in its valence shell. I've always ...
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How to enhance Electrophoretic deposition (EPD) strength?
I have recently attempted to deposit Carbon Black (CB) on carbon cloth. I used a platinum working electrode and a carbon cloth counter electrode. Moreover, the aqueous solution was acetone with one ...
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Why can electrons absorb only certain frequencies and what happens if the energy keeps increasing? [closed]
Electrons can only absorb and/or emit those photons whose frequencies correspond to a certain line in the absorption or emission spectrum of the atom.
It is an all or none case with photons and ...
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Melting Point of Ionic Bonds? [closed]
The melting and boiling point of Ionic Bonds is high due to the strong electrostatic attraction between oppositely charged particles. However Ionic compounds are also extremely brittle. I can't ...
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How many m values are there for the 4f sublevel. In high school so no fancy words please! [closed]
How many m values are there for the 4f sublevel? In high school so no fancy words please!
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How does the electron get back to the ground state at the energy level? [closed]
I have a doubt about how this emission process is carried out in the atom where we have the orbiting electron and we want the electron to return to the fundamental value.
I know that in absorption we ...
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How does an electrons's wave function change when it moves between energy levels?
I'm taking a class on QM and we're simulating the wave function of an electron in a box at the lowest energy level and I'm supposed to change the simulation to show the wave function for the next ...
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The first electron affinity of an atom
I've read that the first electron affinity is always negative, meaning that energy is always released upon the addition of this first electron. However, I don't think this will apply to noble gases. ...
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Why do non-metals not have delocalised electrons, whilst metals do have delocalised electrons?
Why do non-metals not have delocalised electrons, whilst metals do have delocalised electrons? I understand that delocalised electrons is defined as “electrons that are not bound in place to a single ...
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How does hydrogen and oxygen combine to make water? [closed]
When two hydrogen atoms fuse with one oxygen atom to create a molecule of water, each hydrogen atom donates its single electron to the oxygen atom, resulting in 10 electrons for the oxygen, instead of ...
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Why is the first electron affinity exothermic and successive ones endothermic?
I am having trouble wrapping my head around electron affinities. And the textbook explanations aren't very helpful.
So, the textbook says that the 1st electron affinity is generally exothermic. The ...
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In mercury the o shell has 18 electrons but we know that second last shell cannot have more than 8 electrons? [closed]
The last shell has 2 electrons and the second last has eighteen electrons. Byt we know that second last shell cannot have more than 8 electrons. Then how is this possible. Please explain in simple ...
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Electron orbitals
Can electrons be found anywhere within the space described by a 3D orbital "90% of the time" (as stated in my textbook)? But that would mean they can be found right next to the nucleus or in ...
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Why do nuclei move considerably slower than electrons
I've been trying to learn quantum chemistry at an introductionary level. While reading I've found out that the Born-Oppenheimer approximation seems to be the reason for the basic and crucial model of ...
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Length of a 1D box in hexa-1,3,5-triene
Problem
From Hayward's Quantum Mechanics for Chemists [1, p. 36]
2.3. Calculate the wavelength of light that will be absorbed when
a it electron in hexa-1,3,5-triene, $\ce{CH2=CH—CH=CH—CH=CH2},$ is ...
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If you give an electron in a subshell more energy, does it simply "jump" to the next energy level?
Suppose you have an electron in the $\ce{2s}$ subshell of an atom. If energy is given to it, does it simply jump to the next energy level (into the $\ce{3s}$ subshell), or does it move into $\ce{2p}$?
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Which is faster? Electron close to the atom's nucleus or the one far from it and why? [closed]
As we know when the distance between the atom's nucleus and the electron increase the energy of it increase but what about the speed, as physics say that the smaller the radius is the faster the body ...
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Is the given figure correct? Does the electron really flow out as depicted by the arrow? [closed]
Someone up here questioned about the figure and that the arrow is pointless and doesnt make sense? Or is it?
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Terms used to describe the Pauli exclusion principle
This is a very simple question. Today, someone explained to me that the Pauli exclusion principle says that "no two electrons can occupy the same energy state". However, I believe that this ...
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Why does the same electron transition release photons of different frequencies for some elements?
Question: For elements in the same period with different numbers of valance electrons, why does the same electron transition release photons of different frequencies?
Example: For valance electrons ...
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How can Planck’s equation and the wave equation simultaneously coexist with contradicting each other? [closed]
The equations:
E=hf (Planck’s equation, where E is the energy, h is the Planck’s constant and f is the frequency) and
V=fλ (where v is the speed (in a vacuum), f is frequency and λ is the wavelength) ...
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Why is the d subshell only stable when all of its orbitals are filled? [closed]
I was learning about the Aufbau principle and quantum electronic configuration. Here are some of the yet-unanswered queries that I wish to know the answers to.
I discovered that the d subshell is ...
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Why aluminum does not form ammonia complex ion?
I learned in my textbook that zinc forms more stable complex ion with NH3 than OH- because NH3 has only one lone pair and that makes repulsion between d orbital electron in zinc and lone pair electron ...
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What is resonance in actuality? (How does electron sharing, bond formation, and overlapping of orbitals take place in resonance hybrids?) [duplicate]
In this post I got an answer to the question "what is resonance".
What I understand overall is that "resonance is not something really happening physically, it is just an idea to make ...
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What is the energy difference between inner subshells?
For exemple, in silver the energy difference between the 4d 5s subshells is ≈ 4 eV (in the ultraviolet region, that's why it has no color, etc.), but what is the energy difference between some of its ...
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Why does lead gains electrons in the cathode? [closed]
In lead(II) bromide electrolysis, lead is attracted to the cathode and gains electrons. Why does it gain electrons when losing them would be easier since its charge is +2 meaning it would need to lose ...
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Why does Cl- have a higher ionization energy than F-? [duplicate]
I know that F has a higher ionization energy than Cl as the outermost electron is closer to the nucleus. By the same logic shouldn't F- also have a higher ionization energy than Cl-?
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how to make a PEM (proton exchange membrane) out of Nafion Dispersions?
I would like to use a Nafion membrane for a fuel cell project, but the Nafion sheets are hard to integrate. Therefore, I would like a gel type of Nafion that can take the shape of the container I put ...
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What does it mean when we say an atom has infinite energy levels/shells? [closed]
My chemistry teacher told that an atom has infinite energy shells according to Bohr model , where electron reside according to its angular momentum and energy.
But in lower classes/ grades I have ...
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Why is orbital energy not the mean between ionization energy and electron affinity when the orbital has two electrons?
In this question it is asked why ferrocene is colored when the HOMO-LUMO gap seems to be beyond the visible light range. I tried to answer that orbital energies change with electronic transitions and ...
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Why does symmetrical distribution of electrons in d and f orbital lead to greate stability of these or orbitals in comparison to s orbital? [closed]
My high school textbook mentions the following as on of the reason for why Cr and Cu have thier 3d orbitals filled completely before their 4s orbital.
The extra stability of d and f orbital is due to:...
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Confusion regarding 1st and 2nd electron gain enthalpy
$\ce{O}$ has the 1st electron gain enthalpy $\pu{-141 kJ mol-1}$. $-ve$ value implies that energy is released when electron is added to an isolated atom. This also means that if $\pu{141 kJ}$ energy ...
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What is the net gain of charge carriers in a semiconductor if an atom is removed?
In pure germanium, all Ge atoms are bonded with a tetrahedral geometry. It has a band gap and is a semiconductor. If we remove one Ge atom, what type(s) and how many charge carriers will be generated? ...
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Why is polystyrene (PS) an electrical insulator
The reason behind why graphite is electrically conductive is as ancient as the age of the Queen: that, electrons inside the benzene ring are delocalised.
However, if one looks the repeating unit of ...
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How do the spin-matrices change in systems without spherical symmetry?
The (non-relativistic) spin matrices of a free electron, with $z$ as the quantization axis, read:
$$
\boldsymbol{S}_{x}=\frac{\hbar}{2}\left[\begin{array}{ll}
0 & 1 \\
1 & 0
\end{array}\right],...
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What is the paramagnetic susceptibility of sodium at around room temperature?
Proposed solution:
This question comes from Tanner's manual Introduction to the Physics of Electrons in Solids, at the chapter dedicated to the application of the Fermi gas model. The Fermi energy is $...
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Shielding vs electron-electron repulsion
Example of shielding:
(source)
The last electron in the 6s subshell of $\ce {Cs}$ is shielded from the nucleus by the inner electrons.
Example of electron-electron repulsion:
The electron affinity of ...
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What happens during a displacement reaction? [closed]
When Zn metal is added to a solution of Cu(II)SO4, Zinc displaces Cu to form ZnSO4 as Zn is more reactive than Cu. What I don't understand is how.
1- What I'm assuming is: Zn metal collides with [SO4]...
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Observation of deflection in the Cathode ray experiment
In the Cathode Ray Experiment used to discover the electron,
(This is what my textbook says (Grade 11) so if there's any additional parameters that I do not know of I apologize)
The cathode ray tube ...
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A question regarding excitation of electrons in atomic orbital [closed]
In Bohr's model of an atom, the formula used to find the energy between the 2 orbits and wavelength of emitted photon was valid only for single electron species like hydrogen.In the case of a multi-...
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How to calculate ionization energy of an atom provided energy of the electron at ground state? [closed]
It is given that in ground state the energy of electron in hydrogen atom is $-2.18\times10^{-18}\mathrm{J}$. I'm required to calculate the Ionization Energy in kJ/mol
Question for reference:
At ...
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Is an electron's charge arbitrarily called negative? [closed]
In Cosmos Carl Sagan writes
Electrons are electrically charged, as their name suggests. The charge is arbitrarily called negative.
Is this true (I know the book is out of date, like how Titan is ...
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Can an electron be excited to a spin state with s ≠ 1/2?
I used to think that all nuclei have fixed intrinsic value of the nuclear spin quantum number, $I$. For example, $\ce{^1H}$ must have a nuclear spin of $\frac{1}{2}$, $\ce{^{14}N}$ must have a nuclear ...
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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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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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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, ...