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Is the carbon atom in the carbon dioxide molecule partially positive?

I had a question about nonpolar molecules that have symmetrical dipole vectors. Let's take $\ce{CO2}$ as an example. Each of the $\ce{C=O}$ bonds are pulling in the opposite way. My teacher says that this causes all atoms in $\ce{CO2}$ to be equally…
John Hon
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When I burn isopropyl alcohol (IPA), it burns orange. But when I burn ethyl alcohol, it burns totally blue. Why is this?

I burned them in a small aluminium tray. While IPA is burning orange, it produced the smell of soot, but while ethanol is burning blue there isn't any smell. Also, ethanol made the tray really cold when I poured it on the tray before burning it,…
Pushies
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Why does a tetrahedral molecule like methane have a dipole moment of zero?

I was studying chemical bonding when I noticed something odd. We say compounds like $\ce{CCl4}$ and $\ce{CH4}$ have a tetrahedral geometry (which is a 3D structure) but when we talk about their dipole moments, we say they have no dipole moment. We…
gucci
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Can pi backdonation occur on non-metal centers?

The common example of back-donation is the interaction of a CO molecule with a metal center (d-orbitals) on a surface. Can a similar mechanism occur between CO and a non-metal center, like oxygen on a surface (like in an oxide)? Can the p-orbitals…
koroma
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Is it possible to boil a liquid by just mixing many immiscible liquids together?

In open air, when vapour pressure reaches 1 atm, boiling takes place. I read that if we add two immiscible liquids together, the total vapour pressure of the 'mixture' is close to $p = p^*_A + p^*_b$, means that the vapour pressure of the 'mixture'…
TheLearner
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Why does the exchange interaction in Hartree-Fock theory lower the total energy?

In Hartree-Fock theory, the expectation value of the total energy can be written as $$E = \langle\Psi| H |\Psi\rangle = \sum_{a} \langle a| h |a \rangle + \frac{1}{2}\sum_{ab} \big( [aa |bb] - [ab|ba] \big),$$ where the first summation contains the…
Hayden S
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Molecular orbitals used with CCSD(T) geometries

Suppose I am given some geometry data (say, of a water dimer) from CCSD(T). If I were to do a single-point energy calculation to generate orbitals for the system, wouldn't CCSD give something more representative of the correlation in the system…
DC Y
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Why does liquid water form when we exhale on a mirror?

In the descriptions below, I always assume external pressure to be constant at 1 atm, the condition where daily observations are made. 1) When I exhale on a mirror, liquid water forms on the mirror. That's condensation. Obviously, the temperature of…
TheLearner
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Explanation of the strength of phosphorus–oxygen bond

When discussing the Wittig reaction, Clayden's Organic Chemistry (2nd ed.) cites the strength of the P=O bond formed in triphenylphosphine oxide as a driver of the reaction through enthalpy: The P=O bond, with its bond energy of 575 kJ mol−1, is…
Ethiopius
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Why do we call O2 oxygen?

I have been taught that oxygen is a chemical element, in other words a certain type of atom that has 8 protons in its nucleus. So why is O2 called oxygen? It is not a type of atom but rather a molecule.
user70417
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The bond in coordination complexes

This is a very basic question and I'm surprised it only just struck me. The nature of the bond in coordination complexes is a coordinate covalent bond. Only the ligand donates electrons for bond formation between the metal and ligand. Why is it that…
Keerthana A.K.
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Modern alternatives to Gaussian

Specifically, I'm curious if there are any programs which come close to Gaussian in breadth but also take advantage of things such as GPU processing. There's a page on wikipedia that goes through several options but I'd like to get feedback from…
Radu
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standard reference for thermodynamic properties?

I'm a non-chemist attempting to put together a chemistry paper. Up to now I've got my thermodynamic data from various random pdf files found on the web, together with Wikipedia. Now that the paper is nearly finished I need to replace these with…
N. Virgo
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Details of Boltzmann distribution derivation

I have 2 questions regarding the derivation of the formula which calculates the probability of molecules having a particular amount of kinetic energy $E_x$ in a system of $N$ molecules. It states that: $$p(E_x) =…
Phy
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What bond exists in "red oxygen", and can something similar happen with hydrogen?

"Red oxygen" is the nickname for O$_8$. It only exists at extremely high pressures. What kind of bond does it have? Can hydrogen theoretically have something similar at very high pressures too?
DrZ214
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