A chemical bond is an interaction between atoms which results in release of energy. It is one of the most fundamental concepts of chemistry. Existing bonds are broken and new bonds are formed in chemical reactions.
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Software Bond Dissociation Energies, Bond Energy and Hybridization with Polarity
I want to calculate BDE to measure the cost of hybridization of two molecules. There are many examples of protein ligand docking on the internet but there are no examples of hybridization of ligand to ...
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Is energy required to form bonds [phase change]
My question is if any energy is required to form bonds, for instance when there is a phase change?
If I am correct, energy might be required in the beginning, to make the reaction start and then ...
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Calculating bond disassociation energy and bond energy for ATP [closed]
I'd like to calculate Bond Dissociation Energy and Bond Energy for ATP to a similar molecule. What free (at least for academic use) computer programs which natively support and document BDE?
If you ...
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2answers
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When did the atom Theory Become indisputable?
We know that the Greeks were the first scientists (or better, philosophers) to introduce the idea that matter is made up of little “chunks”, and they named these chunks “atoms”. This idea that matter ...
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Electron density definition of single, double, triple bonds?
I was reading this question and the answer by @EricBrown to it and this got me thinking about covalent chemical bonds.
The way I was always taught is that a single bond contains 2 paired electrons, ...
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Why is there a charge on $\ce{COOH^{-1}}$?
The dissociation of formic acid ($\ce{HCOOH}$) is:
$$
\ce{HCOOH -> H+ + COOH-}
$$
Why is there a charge on $\ce{COOH^{-1}}$
though? Is it achieved through:
$$1\times(\ce{C^{4+}}) + ...
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Why does Phosphorous form $\ce{PCl_5}$? [duplicate]
Why does Phosphorous form $\ce{PCl_5}$ ?
The Law of Octet is violated in the formation of $\ce{PCl_5}$
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If magnesium oxide is $\ce{2Mg + O_2 → MgO}$ then why is aluminium sulphate $\ce{2Al^{3+} +3SO_4^{2-} → Al_2(SO_4)_3}$?
Why is it not $\ce{Al_2SO_{12}}$?
Why doesn't the 4 and 3 get multiplied?
Show step by step working of formation of both $\ce{MgO}$ and $\ce{Al_2(SO_4)_3}$.
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Predicting molecular geometry from a formula
Can someone explain the following types of molecules and predict their structure and shape?
It will help my understanding if you could provide an example.
...
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Does SiO2 have polar covalent bonds or coordinate covalent bonds?
First off, I know $\ce{ SiO2 }$ is a network solid. I am looking at its intramolecular forces between the $\ce{ Si }$ and the $\ce O $ molecule. On the one hand, it seems to me that this should be a ...
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98 views
Molecular orbital theory & predicting the stability of a molecule?
A question in my chemistry textbook gives me a list of formulas for molecules and ions and then asks me to determine (using molecular orbital theory) whether or not each would exist in a relatively ...
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4answers
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Covalent Bond/Hydrogen Bond
During the formation of a molecule of water ($\ce{H2O}$), what kind of bond occurs between the elements? I'm studying this subject on my own and from some sources I saw that there is a covalent bond ...
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Materials that resist adhesion with molten glass even when hot
I'm looking for ways to manipulate molten glass with (e.g. bending a heated glass tube).
This article mentions that oxides tend to adhere, hence molten glass to heated stainless steel.
What ...
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2answers
144 views
Bonding and anti-bonding orbitals in the light of time-dependent Schrödinger equation?
In organic chemistry, people draw 2p orbitals like this:
and then they explain how the orbitals combine to non-bonding (π*) or bonding (π) molecular orbitals, like this:
depending on whether the ...
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1answer
29 views
Effect of light on ionic compounds
If i had an ionic molecule which needed 4 eV to break the ionic bond, a 7 eV photon is shot at it. It is absorbed by the molecule and breaks, where do the rest of the energy goes?
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Carbon with 5 bonds?
I've heard that, even though according to Molecular Orbital Theory there is no chance of having nobel gases bonded to each other, it is not totally impossible. For example, under extreme conditions, ...
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63 views
Do metallic bonds contain London dispersion forces?
On our chemistry exam, a question asks "Which force is present between Fe particles? a) Van der Waals b) Metallic"
At first it seemed obvious that it was metallic; however, upon closer reading, it ...
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Could someone explain the photolysis of water? [closed]
Could someone please describe the photolysis of water?
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1answer
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What is charge density?
For example, Magnesium has a higher charge density compared to Sodium, therefore its metallic lattice is stronger and it has a higher melting point. Does that mean that Magnesium has more protons and ...
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1answer
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Bent molecular geometry of water
Could you please explain how the bent molecular geometry of water is due to hydrogen bonding? I was under the impression that it was because of the lone pairs (VSEPR Theory).
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Help understanding localized bonding theory
So I understand molecular orbitals and how to do VSEPR models, but I seem to be struggling with understanding localized bonding theory and how to do hybridizations. After drawing the initial lewis ...
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2answers
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Classical reason for good heat conductance in diamond?
My teacher in my physics course attributed this effect to phonons, more here, but I am skeptical about this argument, it feels like he is overlooking the whole question -- what about with Silica that ...
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0answers
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Is it okay for a sulfite ion to have 10 electrons around the sulfur? [duplicate]
Possible Duplicate:
Can an atom have more than 8 valence electrons? If not, why is 8 the limit?
I was watching this youtube clip ( http://www.youtube.com/watch?v=XY1XLgHUAIQ ) in which a ...
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125 views
Lewis structures of H2(C)xCH2 molecules
I need to calculate the angles between CCC, CCH, HCH in the following molecules:
$H_2 CCH_2 $ , $H_2 CCCH_2 $ , $ H_2 CCCCH_2 $ .
If I'm not mistaken, the Lewis structures of all of these molecules ...
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Lewis structures of molecules containing oxygen
As far as I know, when writing Lewis structures for molecules, we need to consider the octet rule and the valence electrons each atom has.
But, if we take for example, the molecule $ Cl O_2^- $ , we ...
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188 views
Why don't atoms with expanded valence shells have a formal charge?
I'm working through Chemistry - Principles and Practice, 3rd Edition and I have few complaints so I don't think it's the text. At one point, I was asked to draw the Lewis structure, with formal ...
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113 views
How to determine stable electron states in ionic and covalent bonds?
I'm working on a program that needs to determine if a bond between two or more elements will result in a stable state. I understand at a high-level how to fill electron subshells using the Aufbau ...
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2answers
131 views
Are there any molecules with delta bonds in their ground states?
When looking at excited states of molecules, $\delta$ bonds are relatively common, but I've never come across a molecule with a $\delta$ bond in its ground state.
Are there molecules with $\delta$ ...
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3answers
376 views
Fundamental forces behind covalent bonding
I understand that covalent bonding is an equilibrium state between attractive and repulsive forces, but which one of fundamental forces actually causes atoms to attract each other?
Also, am I right ...
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331 views
Bonding in $\ce{C2}$, a carbon-carbon quadruple bond?
Carbon is well known to form single, double, and triple C-C bonds in compounds. There is a recent report (2012) that carbon forms a quadruple bond in diatomic carbon, $\ce{C2}$. The excerpt below is ...
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3answers
242 views
What is natural bond orbital theory used for?
My understanding is that the NBO methodology transforms the molecular orbital picture of a molecule into a collection of pairwise interactions (bond orbitals). This is obviously handy for didactic and ...
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4answers
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What is the difference between physical and chemical bonds?
If you characterize the chemical bonds to two categories physical and chemical bonds, how do you do it? Aren't all bonds chemical and physical?
From the freedictionary.com, chemical bond:
Any of ...
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What makes banana bonds possible in diborane?
Diborane has the interesting property of having two 3-centered bonds that are each held together by only 2 electrons (see the diagram below, from Wikipedia). These are known as "banana bonds."
I'm ...
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What is the difference between cross-linked bond and secondary bond in polymers?
There are two kinds of bonds between polymers in solid material: primary and secondary. Primary bonds can be also called cross-linked bonds. What is the difference between the two (strength, type, ...
