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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Bond Angles and intermolecular interactions

It's fun to consider bond angles of molecules in isolation. For example, what is the number of different bond angles exhibited by the most polar form of $\ce{SIBrClF2}$? However, can bond angles ...
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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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Is this the correct mechanism of the formation of the nitronium (NO2+) ion from sodium nitrate and sulfuric acid?

I am currently working on a mechanism for forming paracetamol (or N-(4-hydroxyphenyl)-ethanamide). The typical reaction to nitrate the phenol (starting product) is $\ce{NaNo3}$ with a catalyst of ...
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What is the bond angle of H2O?

I have been trying to find out the bond angle of H2O, but every site I visit has a different answer. So far, I have found the following angles listed: Site 1: 104.4º Site 2: 107.5º OR 104.5º, ...
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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 ...
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Oxidation state of HOF

Here is a structure of $\ce{HOF}$ (known as Hypofluorous acid). So there is a fact about Hypofluorous acid that I've been wondering about so many times before that what should be the oxidation ...
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Why does nitrous acid exhibit (unexpectedly) different bond angles?

Data Point 1 - quantum chemical calculations http://nzc.iap.ac.cn/uploadpdf/Wang_et_al._CSB_2007a.pdf Key points in paper: There is some sort of interaction between the hydrogen and the terminal ...
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Sulfur Trioxide - Ionic Character

I am told that the sulfur trioxide molecule exhibits charge separation because of poor p-orbital overlap. Sulfur's 3p orbitals are much bigger than oxygen's 3p orbitals, and thus the $\ce{S=O}$ bond ...
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Peroxide Linkages

Why are peroxide linkages generally weak? Is it due to Coulombic repulsions? I can't see how placing two oxygens with high degrees of partial negative character next to each other is a good thing in ...
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Nitric Oxide Dimerization

This is the molecular orbital diagram for nitric oxide: Now, we know that nitric oxide can dimerize. However, why does nitric oxide dimerize as to form an $\ce{N-N}$ bond? Why not an $\ce{O-O}$ ...
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Nitrogen dioxide dimerization

$\ce{NO}$ can't dimerize and that is explained because the free electron is in an antibonding orbital. The same is true for $\ce{NO2}$, but it can dimerize, how?
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Why does HCO₂⁻ exhibit delocalized bonding while CO₂ does not?

$\ce{HCO_2^-}$ exhibits delocalized bonding and $\ce{CO2}$ does not? What I am confused about is, that both of them have resonance structures. Therefore, why doesn't $\ce{CO2}$ exhibit delocalized ...
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How to draw resonance structures for CH3COCN

What are the resonance structures of $\ce{CH3COCN}$ molecule?
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Trends in bond angle of H2O , H2S, H2Se ? How to explain?

I know that bond angle decreases in the order H2O, H2S and H2Se. I want to know the reason. I think this is because lone pair repulsion but how? Please explain.
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Why unbonded electrons exits in pair

Basically the term which we use to refer them is lone pair. In Lewis structure why we represent those unbonded electron in pairs. Like here (structure of SO2) Here if we assume both the unbonded ...
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IBrF2 - van der Waals repulsions - and number of unique bond angles

I understand that the molecule $\ce{IBrF2}$ is T-shaped, with three ligand atoms and two non-bonding pairs. However, how many unique bond angles can this molecule exhibit? My professor argues for ...
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Do filled Orbitals also hybridize?

Recently I was watching a video on Valence Bond Theory, on the MIT Open-Course youtube channel. The teacher there said that for hybridization to occur, electron promotion from fully filled orbitals to ...
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Why Aren't Chlorides Of The Noble Gases As Prevalent As Their Fluorides?

I can't find the answer to this question on this SE website, and I apologize for the repetition if it has been answered before. It is my understanding that compound formation has only been observed ...
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What is the proper Lewis structure for HCOOH?

I tried to draw the Lewis structure of $\ce{HCOOH}$ but I didn't get the correct representation. As you can see in the picture below, at no. 1, I put $\ce{C}$ as the central atom because it has less ...
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The definition of formal Charge

Ok, most people including me know that formal charge is just a book-keeping tool. I know how to calculate it, apply it to Lewis structures etc etc. But I am confused in its very basic definition which ...
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Identical bond angles

Is it possible to incorrectly predict that two bond angles are different from van der Waals repulsions alone? I'm thinking that because bond lengths differ when different atoms are involved that we ...
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How can a chemical structure be stored in a matrix?

How do I represent a chemical structure in a matrix format in Matlab? Can I input a chemical structure into Matlab using the S.M.I.L.E.S notation? I have to specify the connectivity of different ...
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What is the difference between a bond, force, and interaction?

I am trying to explain why some solids are more soluble in water than others: So the energy released from the formation of bonds between the solid solute molecules and water molecules compensate the ...
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What affects bond angles?

I have three factors in mind: 1) vdW repulsions 2) Bond length 3) Electron-electron repulsions. I know that vdW repulsions between ligand atoms push the atoms apart. And bond length obviously ...
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Determining covalent bond strengths without hybridisation

Assuming pure $\ce{2s}$ and $\ce{2p}$ orbitals of carbon are used in forming $\ce{CH4}$ molecule, which of the following statements is false? (single choice question) Three $\ce{C-H}$ bonds ...
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How does the pyramidalization effect the bonding angles in a distorted octahedral environment?

This is a follow up on "Generally Octahedral - Meaning?". Since Dissenter asked in the comments to my answer: I'm not sure why the $\ce{F_{eq}-S-F'_{eq}}$ bond angles would be compressed, even if ...
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Chemical bonding - lattice energy

Question: Why is ionic lattice energy inversely proportional to the radius of the atom? Most heterogeneous covalent molecules are polar to some extent. The degree of polarity, or the dipole moment, ...
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Why is the bond angle H-P-H smaller than H-N-H?

$\ce{N}$ & $\ce{P}$ are along the same group. $\ce{NH3}$ and $\ce{PH3}$ have one lone pair and both the central atoms are $\ce{sp^3}$ hybridized. But inspite of that, the former's bond angle is ...
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Difference between backbonding and hyperconjugation and conjugation [closed]

What is the difference between backbonding and hyperconjugation and conjugation? I mean the basic differences as all are concerned with donation of electrons. What is the most striking effect of each ...
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207 views

Why is Aluminium Chloride a Lewis Acid if it's an ionic compound?

In my textbook it says in the reaction $\ce{AlCl3 + Cl- -> AlCl4-}$, Aluminium Chloride ($\ce{AlCl3}$) has six valence electrons and accepts a lone pair from $\ce{Cl-}$, but wouldn't that mean the ...
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Polymer Crystallinity

See the following question: I think the answer is A because of the hydrogen bond in the side group, thus the degree of secondary bonding between parallel chain segments is higher. Is my thinking ...
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Can there be a reaction in which nuclear fission or fusion takes place along with atomic recombination?

I can't make out myself whether a nuclear reaction reaction can occur along with a chemical reaction involving bond formation? Can any one suggest an example of this, please?
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How can sulphur and phosphorus expand their octet

There are many compounds, in which the stability of a molecule is not governed by the presence of octet configuration in central atom. In most of the cases the central atom is generally sulphur or ...
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Can I perform electrolysis without electrolyte? (with distilled water)

When performing electrolysis at home, I usually used salt water as electrolyte. The problem is, that this method also produces chlorine and chlorine is aggressive to both humans and electrical ...
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How is the charge of covalently bonded atoms determined?

My question is about what it is - at the subatomic level - that determines the charge on atoms which participate in covalent bonding in reality. I understand that formal charge is just that - it's a ...
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Orbital Overlap Factors

I have discerned these factors affecting orbital overlap: 1) Symmetry 2) Type of orbital 3) Nodes along the internuclear axis 4) n quantum number of the atomic orbitals - the number of shells of ...
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Why is hydrogen sulfate put together as it is?

I recently looked up hydrogen sulphate ($\ce{HSO4-}$) to see how it's put together, and found this image of methyl hydrogen sulphate: I'd assume that hydrogen sulphate looks the same, but without ...
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Why is H2S more polar than HCl?

From EN alone we might expect HCl to be more polar but a book says that the bent structure of H2S gives rise to its polarity - which is also apparently more than HCl. Why? Does this have to do with ...
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Bonding in the phosphate ion

I'm looking for an explanation of the bonding in the phosphate (PO43−) ion: (Image courtesy of Wikipedia) Phosphorus (15P) - being the fifteenth element - has fifteen electrons, five valence ...
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Can Entropy Increase During Bond Formation?

Recently the question was asked, "Is Bond Formation “Strictly” Exothermic?" As a corollary to that question, what is the relationship between entropy and bond formation? Does the entropy of the bond ...
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Why does calcium carbonate decompose into calcium oxide?

Why does calcium carbonate, when heated strongly, decompose into calcium oxide and carbon dioxide? What is the mechanism? Can someone illustrate the means by which this happens? What ...
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Endothermicity of Reaction

Regarding this question, how can one solve this without access to thermodynamic data? I suppose we should keep the following information in mind: 1) Double bonds are not double the strength of ...
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Existence of Hyponitrite Molecule

Does the hyponitrite molecule exist? I know the hyponitrite ion exists (http://en.wikipedia.org/wiki/Hyponitrite) but what about the molecule? I have found no reference to the molecular form on ...
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Is Bond Formation “Strictly” Exothermic?

Is bond formation "strictly" exothermic? The IUPAC definition of exothermic doesn't make any reference to bond formation. However, I have seen the aforementioned statement before - that bond formation ...
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Why are radicals unstable?

Why are unpaired electrons especially reactive? Does pairing electrons decrease the reactivity of the electrons? But then doesn't forcing two electrons into the same orbital cost energy?
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Why is the C-Br bond considered polar?

Why is a C-Br bond considered polar? From electronegativity considerations, both carbon and bromine have very similar electronegativities - 2.5 and 2.8 - respectively. Nonetheless, I am told that ...
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Is the bond enthalpy of S-O stronger in SO₃ or SO₃²⁻?

Can you please explain the difference between the bond enthalpies in sulfurtrioxide $\ce{SO3}$ and the sulfite anion $\ce{SO3^{2-}}$?
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From liquid to solid by beating

I understand how liquids can become solids by decreasing temperature. To my understanding this is because the molecules slow down and are able to form bonds. However, I'm having problems ...
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Is the amount of phenolic in phenol-water solution related to amount of hydrogen bonding between phenol and water in that solution?

Is the amount of phenolic in phenol-water solution related to the amount of hydrogen bonding between phenol and water in that solution? Does phenolic in phenol-water solution/ hydrogen bonded ...
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Why is silicon oxide giant covalent structure?

Why is silicon oxide giant covalent structure? Why it doesn't bond like carbon dioxide? Thank you