An orbital is a theoretical stable standing waveform shape in which one or two electrons can be found orbiting the nucleus of an atom.

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Why is copper (II) coordination number so big?

Consider tetraaminecopper (II) ion. $\ce{[Cu(NH3)4]++}$ or $\ce{[Cu(NH3)4(H2O)2]++}$ Copper (II) ion has electron configuration $\ce{[Ar] 3d^9}$. How do the 4 electron pairs from ammonia atoms form ...
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1answer
53 views

Which orbitals of the hydrogen atom are degenerate for n=3?

Here's the link to the picture of the question. The answer says its E. All of them. First of all isn't there only 1 electron in hydrogen? And how could the s orbital be degenerate? Doesn't ...
4
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2answers
174 views

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 ...
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62 views

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 ...
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31 views

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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1answer
134 views

why do 2 atomic orbitals form 2 molecular orbitals?

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 ...
2
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1answer
36 views

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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1answer
59 views

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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63 views

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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1answer
33 views

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 ...
2
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1answer
98 views

How to explain 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 MOT be used to explain it ?
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27 views

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 ...
5
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1answer
169 views

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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1answer
75 views

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 ...
7
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1answer
73 views

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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1answer
49 views

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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1answer
184 views

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, can be approximated by a linear ...
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1answer
52 views

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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1answer
85 views

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?
6
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1answer
150 views

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 ...
3
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1answer
89 views

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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0answers
96 views

Plotting Angular Wave Functions of Orbitals

I'm taking an introductory Chemistry class, and we are asked to plot the angular wave functions for orbitals. What exactly does the angular wave function convey or represent? I'm very confused as to ...
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1answer
56 views

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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26 views

Orbital representations [duplicate]

The usual 'orbitals' that we draw are drawn with the axes shown and everything. But orbitals are really only 1 electron wave functions of 3 dimensions... Therefore, they can't be plotted as such in ...
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2answers
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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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1answer
54 views

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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1answer
643 views

An atom of silicon in its ground state has how many electrons with quantum number l = 1?

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 l ...
4
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1answer
109 views

Asymmetry in trigonal bipyramidal geometry

I teach an MCAT course in chemistry. I like to explain VSEPR by saying.. first, imagine arranging electron pairs around the central atom so they are maximally distant from each other, and uniformly ...
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1answer
181 views

Show the vibrational frequency of F2- is much lower than that of F2

Basically I need to draw the molecular orbital for $\ce{F2}$ and then answer a bunch of questions about it. I have drawn it correctly, as far as I know, but I don't know how to use it to show that the ...
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2answers
2k views

Why do atoms “want” to have a full outer shell?

Okay, so I know that this is about filling the orbitals of the atom, and I understand that. What I don't understand is why? For example, an Oxygen atom has 8 protons and 8 electrons spinning around ...
4
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2answers
562 views

Periodic trend in difference of energy between the s and p orbitals

Why does the difference of energy between the 2s and 2p orbitals of the second period elements increase with increasing atomic number? Does this difference increases by moving down a group, e.g. is ...
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0answers
33 views

How can I tell what colour an element will be? [duplicate]

Previously in my Chemistry education, it was required of us to memorise the colour changes some elements, especially transition metals, go through. Currently we learning about electron configuration ...
4
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1answer
611 views

Symmetry labels for orbitals

What are the symmetry labels for the p and d orbitals of $\ce {[PtCl4]^{2-}}$ ? I understand the concept of symmetry labels for molecules. some explanation of how it applies to orbitals would be ...
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1answer
97 views

Unequal ionization energies of methane

Why does methane have two different ionization potentials? How does this work? I understand that MO theory predicts C-H bonds of differing strength, while hybridization predicts C-H bonds of varying ...
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Evidence of orbitals?

How do we know that there are different types of orbitals? For example, what evidence is there for the existence of p orbitals instead of there being multiple s orbitals (for example, why isn't the ...
3
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1answer
104 views

Why do higher orbitals have more energy?

I have seen in textbooks and videos that an electron must absorb energy (become excited) to enter a farther-away orbital. The amount of energy that must be gained is equal to the difference in energy ...
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1answer
91 views

Whats the difference between ionization energy and orbital energy?

If you look at the trend in orbital energies as you go across a period the pattern is clear (orbital energy decreases with increasing effective nuclear charge) and, to my knowledge, it has no ...
4
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1answer
117 views

How do electrons travel through nodes

I understand this is a basic question, but I'm having such a hard time wrapping my head around it. I'm trying to avoid thinking about it as an actual "particle" but as a wave, but that confuses me ...
3
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1answer
69 views

Do electrons only fill 'spin up' first? Or could it start filling 'down spins' first?

Due to Hund's rule, electrons start filling up the orbitals without pairing up. When this is happening, do the electrons all fill up the 'up' spin? Could they fill in the 'down' spin? Why do they ...
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2answers
52 views

Resonance stabilization and size of ligand atoms

I am told that for these two molecules, one of them is not as resonance stabilized as the other. Apparently it's the chlorine one, and it's because of the mismatch in the size of chlorine and carbon. ...
5
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1answer
494 views

Why is one lobe of an sp3 hybridized orbital smaller than its other half?

A hybrid sp3 orbital is drawn with one lobe smaller than its other half, the latter which is of equal size when drawing the p orbital. Why is it so?
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Which d orbitals of sulphur take part in the pi bonds of SO3?

In $\ce{SO3}$ 2 $p\pi-d\pi$ bonds are present. But which 'd' orbitals of sulphur take part in these $\pi$ bonds ? The answer says $d_{xy}$ and $d_{yz}$, someone also told me that crystal field ...
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Why are DCM and Chloroform so resistant against nucleophilic substitutions?

In the book Organic Chemistry by J. Clayden, N. Greeves, S. Warren, and P. Wothers I found the following reasoning: You may have wondered why it is that, while methyl chloride (chloromethane) ...
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1answer
77 views

What are the Waves Modeling when Referring to the Atomic Orbitals

It is taught that the orbital shapes derive from wave functions with different numbers of nodes. For example, the "s" orbital comes from a wave that has one node. But what are the waves modeling? A ...
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2k views

What is Bent's rule?

I'm all bent out of shape trying to figure out what Bent's rule means. I have several formulations of it, and the most common formulation is also the hardest to understand. Atomic s character ...
5
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3answers
118 views

Can electrons switch orbitals within a shell?

I know that electrons can move from say 2s orbital to an unoccupied 2p orbital, as in Carbon atom which can form 4 bonds this way. But I want to know is it possible for an electron say in orbital 2p ...
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2answers
829 views

Difference between actual position of electron and Radial Distribution Probability

Its known that the radius of maximum probability of 2s orbitals is more than that of 2p orbitals. It means that the maximum probability of finding an electron in an 2s is further away from electron ...
5
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1answer
108 views

Electronic model with highest prediction rate

Among many models, including the valence bond model (VB) or the molecular orbital (MO) model, which are the ones with best predictive power? (e.g. the MO is thought to predict spectroscopic ...
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525 views

When is it true that more nodes equals higher energy?

Consider all the MOs of some isolated molecule. (It could be a single atom too; I'll use MO to refer to AOs as well.) Number them in increasing order of the number of nodes (node = surface where the ...
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Counting Nodal Planes in cyclopropane

The energy of molecule orbitals increases with more nodal planes. W1 (in the attached picture) has no nodal plane. I'd like to know how to draw the nodal planes in cyclopropane molecule orbitals but ...