Questions tagged [orbitals]
An orbital is a one-electron wavefunction, usually derived by solving the Schrodinger equation. This tag applies to questions about all forms of orbitals; additionally, questions about the construction and properties of molecular orbitals should be tagged with [molecular-orbital-theory].
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Which orbitals of the hydrogen atom are degenerate for n=3?
Which of the following orbitals are degenerate in the hydrogen atom with $n = 3$?
A. II and III only;
B. I and IV only;
C. I, II, and IV only;
D. II, III, and IV only;
E. all.
The ...
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Does hyperconjugation and induction always have the same effect?
My professor does not believe in the hyperconjugative effect. Instead, we only consider inductive effects.
So do both effects have the same general effect? I know for methyl groups both have the ...
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Why are sp hybridized carbocations high energy?
You don’t see carbocations on double bonds very much, and here's a good reason: compared to sp3, there is more s character in the orbitals, so the empty orbital is held more closely to the nucleus. ...
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Totally confused about the location of "s,p,d,f" Orbitals inside the atom
Here is the other crazy question... I know that electrons revolve around nucleus in their orbits.But my question is "how the orbitals are located in the orbits? Do they really posses Spherical, dumb ...
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Why does symmetry have to be maintained in molecular orbitals?
Using the example of $\ce{XeF4}$:
What is the physical explanation enforcing the symmetry of the $\ce{1b_{1g}}$ orbital on the fluorine atoms? Why isn't the symmetry of a nonbonding orbital arbitrary?...
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Hydrogen cyanide - a Lewis acid?
I am told that $\ce{HCN}$ is a Lewis acid.
From what I understand a Lewis acid possesses (an) empty orbital that is accessible to attacking nucleophiles.
Does $\ce{HCN}$ have any empty orbital(s)? ...
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Why are d-orbitals required/used for hypervalent molecules (where the central atom has expanded its octet) [duplicate]
Period 2 elements like carbon, oxygen and nitrogen cannot expand their octet because they cannot make use of d orbitals in that energy level (they don't exist). However, period 3 elements like sulfur ...
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Why do two atomic orbitals form two molecular orbitals? [duplicate]
According to molecular orbital theory, two atomic orbitals form two molecular orbitals analogous to waves combining constructively or destructively but how can a wave combine destructively and ...
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Is shielding of electrons really best described as shielding or is it really Coulombic repulsion between electrons?
For example, take the 2s electron in lithium - is the reason that it's ionisation energy is lower than would be expected if "shielding" didn't occur at all because the 1s electrons shield the ...
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What is the usage of orbitals more complex than f orbitals?
Every high school learner, in each corner of the world, faces the lesson History of Atom during his courses, just as I did. We learned about s, p, d and f orbitals, though there were no signs of ...
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About the meaning of the names of f orbitals
Our chemistry teacher encouraged us to study the history and naming of the orbitals on the web. (actually, our textbook did, but that's irrelevant to the problem) I easily could find the reason behind ...
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Determine which orbitals will form hybrids with one another
I've been teaching myself chemistry, so any help is greatly appreciated. I've been reading an online tutorial that claims the two orbitals that merge in Aluminum trihydride are 1 orbital of 2s and 2 ...
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What is the Difference Between the Conjugate Effect and the Inductive Effect?
As the title suggests, what is the difference between the conjugate and the inductive effect in organic chemistry.
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The effect of hyperconjugation on the stability of alkenes with MO theory
Hyperconjugation stabilizes carbocations and that makes sense because electrons are given to the empty p orbital.
But how does it stabilize alkenes? Can molecular orbital theory be used to explain it?...
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Non stationary effects of molecular orbitals
We have been learning a bit about molecular orbitals in class.
However, we have always considered things under a quasistatic approximation.
What are some effects that can only be explained by not ...
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Why do the d orbitals have these notations?
Why do the d orbitals have the following notations: $xy, yz, xz, z^2$ and $ x^2-y^2$? What do they represent in their wave-functions?
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Why can't the conjugate base of benzoic acid be stabilized by conjugation with the aromatic ring?
All the carbon and oxygen atoms are sp2 hybridised and can have a p orbital in the correct plane yet only conjugation of the COO- group occurs. I can't think why. I can't draw resonance structures for ...
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Properties of f-orbitals
I am not a Chemist, but I took enough undergraduate Chemistry classes to understand the basic properties of s, p and d orbitals and how the behaviour of electrons contributes to different kinds of ...
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Which group does germanium belong to?
$\mathrm{Z= 32}$
$\mathrm{1s^2\ 2s^2p^6\ 3s^2p^6d^{10}\ 4s^2p^2}$
According to me it belongs the $\mathrm{IV\ B}$ group since it has the $\mathrm{d}$ completed, but it belongs to $\mathrm{IV\ A}$. ...
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The "rules" for LCAOs in Molecular Orbital Theory
In our course on physical chemistry, which involves MOT, we have been taught that in the LCAO approach, the wave function for a molecule … say hydrogen ion ($\ce{H2+}$), can be approximated by a ...
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how many electrons are in the second subshell of this element?
first of all sorry if I have some mistakes in my "chemistry words", I'm Iranian and I know the Persian terms but only some of the English ones.
So suppose we have an element (x) with the atomic ...
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Why is there an exponent 4 after the brackets in sp3?
My professor wrote an electron configuration for carbon as: 1s2 (sp3)4
I thought it was just 1s2 sp3 where did the 4 come from?
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How does the radial distribution function of Vanadium differ from that of Calcium and how does this affect the ionic electron configurations?
When Vanadium is ionised it loses the 4s electron first, meaning that it's 3+ ion has a different electron configuration to Calcium despite it being isoelectronic. Can it be explained in terms of ...
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Why are all the orbitals that have the same principal number in Hydrogen degenerate?
In hydrogen, all orbitals with the same principal quantum number 'n' (1,2,3...) are degenerate, regardless of the orbital angular momentum quantum number'l' (0,1...n-1 or s,p,d..). However, in atoms ...
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Orbital angular momentum
For hydrogen atom, L^2 and Lz can be obtained as eigenvalues for a particular wave function. But that does not completely specify the angular momentum vector. How to get about this problem?
Also, in ...
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Finding the irreducible representation which an orbital transforms under [duplicate]
I have some major confusion on irreducible representations. An example of a problem I have is
Based on the character table for the point group of each of the follwing molecules, which irreducible ...
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Difference between shells, subshells and orbitals
What are the definitions of these three things and how are they related? I've tried looking online but there is no concrete answer online for this question.
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Hybridised orbitals
What determines which type of hybridisation (sp3/sp2/sp) a molecule will take? Methane/ethylene/acetylene all have the same electron configuration but undergo different different types of ...
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How many electrons with l = 1 does Si in its ground state have?
I was solving practice problems for electron configuration and periodic table, and I got stuck through a question:
An atom of silicon in its ground state has how many electrons with quantum number $...
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Can we compare the electron shells with the orbits of the planets around the sun?
Can we compare the electron shells with the orbits of the planets around the Sun, is this a good comparison?
Is it true for all the atoms that they can have only 2 electrons on the first shell, but ...
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