Molecule Definition and 462 Threads

The Bohr atom gave the answer to the spectrum of the hydrogen atom. But the spectra of stars contains many absorption (and sometimes emission) lines, corresponding to most atoms (up to iron, I believe). And atmospheric absorption is also due to absorption of some molecules, such as water...

Hello, I'm trying to calculate what is the effective volume of a molecule of N2 in the most precise way possible (I'm a high school student so "in the most precise way possible" is probably not that precise considering my lack of advanced mathematical knowledge). What I want to know is, if I had...

In ##t = 0##, we have ##\rho (0) = | + \rangle \langle + |##. The time evolution of the density matrix is given by ##\rho(t) = e^{-i\hat{H}t} \rho (0) e^{i\hat{H}t}## (I am considering ##\hbar = 1##). I can write the state ##| + \rangle ## as a linear combination of the eigenstates of the...

We can consider the ammonia molecule ##NH_{3}## a two level quantum system, because the ##N## atom can be either above or below the plane formed by the three ##H## atoms. We call these states ##|+ \rangle## and ##|- \rangle##, respectively. The hamiltonian in the basis ##(|+ \rangle, |-...

Dear Forum Members, I am a molecular biologist. One of my projects is focused on the identification of a protein that interacts with a known organic molecule. Namely, I try to chase a transmembrane protein that is known to transport one organic acid. If possible, I would like to get an idea on...

Hi All, The Potential Energy for two chemically bonding atoms is defined by ,U=1/2(k*q1*q2)/r So it means that when the atoms approach each other then, their Potential Energy will increase. Where am I doing wrong? I will be thankful for help!

Cobalt(II) Copper(II) Copper(II) tetrachloro complex Chromate Vanadyl(V) (pervanadyl) Dichromate Can these metallic ions make up a certain molecule?

Homework Statement I have the diatomic molecule hamiltonian given by: $$-\hbar^2/(2\mu)d^2/dr^2+\hbar^2\ell(\ell+1)/(2\mu r^2)+(1/4)K(r-d_0)^2$$ Now it's written in my solutions that if we put: $$K\equiv 2\mu \omega_0^2, \hbar^2\ell(\ell+1)/(2\mu d_0^4)\equiv \gamma_{\ell} K, r-d_0\equiv...

So I love Quantum but unfortunately I don't have much idea of what its about. I would love to grasp the concept better. Can anyone discuss it with me?

Homework Statement The ammonium ion NH4+ has the shape of a regular tetrahedron. The Nitrogen atom (blue sphere) is at the center of the tetrahedron and the 4 Hydrogen atoms are located at the vertices at equal distances L from the center (about 1 Å). Denote the mass of the hydrogen atoms by Mh...

Hello 1. Homework Statement The dipole moment of an ammonia molecule is ##d_0=5*10^{-30} C.m##.If we apply a static electric field of ##\mathcal { E }=1*10^{6 }V*m^{-1}## to an ammonia molecule initially in the state ## |ψG⟩## where the nitrogen molecule is considered to be on the left,we make...

Is C a mono-atomic molecule? As I know molecules made of two or more than two atoms such as O2, N2, HCl etc but what's about carbon? like below C + O2 = CO2 Could you please explain the matter so that I can understand the concept well?

Homework Statement How to calculate the maximum charge of an atom or a molecule? As we know the equivalent weight = atomic weight / maximum charge Al, Ca and O2The Attempt at a Solution Al, E = 27/3 = 9 Ca, E = 40/2 = 20 O2, E = 16/2 = 8 I see on the books that the charges of Al, Ca and O2 are...

Is there any difference between 1 mole of CH4 and 1 molecule of CH4? or they mean the same thing?

Homework Statement Suppose there is a tank filled with water and a piston of area S exerts a force F on the water. Suppose I divide the water boundary touching the piston to - N small equal " square " molecules. Then , the force on the upper face of each molecule is F/N . Also, the area of...

Hi, I am looking at how molecules with hydrophobic and hydrophillic properties move and orientate themselves in water. If I have say a PFOS molecule... The hydrophobic part (the perfluoroalkyl group - the carbon chain) will move to the liquid surface but the hydrophillic part (the sulfonate...

Homework Statement Considering the molecule of ##C_2^+## in an excited state with valence configuration ##2\sigma_g^2## ##2\sigma_u^2## ##1\pi_u^2## ##3\sigma_g^1##. Finding all the possible term symbol. Homework Equations Term symbol ##^{2S+1}\Lambda## ##L=0 \rightarrow \Sigma## ##L=1...

I am wondering if anybody knows how to calculate the theoretical relative permittivity of a molecule (1) using the theoretical configuration and values that are easily accessible (2). I am also wondering what the technique would be. In my pharmaceutical reaction class and also O-chem 2 we have...

Which one is correct below 1. a single molecule of H2O 2. a single atom of H2O (if this one is correct then what does it mean?)

As we know, in the case of an atom, 1 mole of C = 6.023 X 10^23 C atoms and in the case of a molecule, 1 mole of C molecule = 6.023 X 10^23 molecules. as we know, atoms are used to make molecules, So can I say 1 mole of C atoms make 1 molecule of C because what we get If we break 1 molecule of C...

I am a longtime producer and host of a children's radio show on our local public radio station. It's springtime and the rivers are running and I'm working up a little bit of shtick about water for the show. Water molecules are among the smallest, and one goal of the piece is to relate the size...

Homework Statement If CO = 10 moles, then how to find moles of O in CO molecule? Homework Equations If CO = 10 moles, then how to find moles of O in CO molecule? The Attempt at a Solution I don't know how to proceed

Homework Statement Homework EquationsThe Attempt at a Solution Considering the molecule as collection of two spherical atoms whose centers are joined such that they touch each other, Then, as a rigid body the system has 6 degrees of freedom and around the axis joining the two centers, the...

Homework Statement The carbon dioxide molecule can be considered a linear molecule with a central carbon atom, bound to two oxygen atoms with a pair of identical springs in opposing directions. Study the longitudinal motion of the molecule. If three coordinates are used, one of the normal...

This question is regarding equation 6.59 in Classical Mechanics Goldstein 3rd edition. I don't understand how he reaches that step. He says he does by inverting 6.41. Is he taking the transpose matrix composed of the eigen vectors by meaning inversion ? I thought I could upload the screenshot...

I noticed that different brands of espresso coffee have different effect on my nervous system. Some are really good in the sense that they wake me up and make me feel fresh and dynamic, while others do nothing, and others make me really jumpy and nervous and stressed. Why is that? I am not good...

Homework Statement n/a Homework Equations n/a The Attempt at a Solution n/a Just a question. I keep seeing that in SN2 reactions, sometimes a molecule is quenched by H2O or H3O. I've seen it turn an O- into an OH and also a heteroatom into an H. What exactly is going on here?

Is O3 molecule polar or non-polar? I am confused. If it is molar, could you explain why? Thinking you.

Homework Statement Consider an ##H_2## molecule where the protons are separated by a wide distance R and both are located on the z-axis. Ignoring the spin degrees of freedom and treating the dipole-dipole interaction as a perturbation, use perturbation theory to estimate an upper limit for the...

https://www.quantamagazine.org/lifes-first-molecule-was-protein-not-rna-new-model-suggests-20171102/

Homework Statement For the molecule CHCl3, a) Draw the electron dot diagram and structural formula b) predict the shape c) predict whether it is polar or non-polar, and justify your prediction. Indicate the positive and negative poles. Homework Equations none The Attempt at a Solution [/B]...

Imagine attaching electrodes to a complex sample, e.g. a semi-conductor or a single chemical molecule, leading to some electric current. Can we decompose this electron flow into local flows? - like locally attaching amperometer and counting what fraction of electrons flow directly between given...

I am looking for litterature that derives mathematically the total energy in a ##H_2## molecule by using quantum physics. Anyone knows a book they can recommend. I have seen derivations for helium atom for example: http://farside.ph.utexas.edu/teaching/qmech/Quantum/node128.html I need...

Hi, I'm stuck on a problem. I have this function that represents the velocity: f(v)=v2e(-mv2)/(2kT) T is the temperature and equals 293.15K m = 4.65 .10-26 kg k = 1.38 .10-23 J/K The problem wants us to find the derivative of the function. I found: df/dv= (2v)...

A diprotium molecule might undergo tunnelling to fuse by two reactions: p+p→d+e++νe p+p+e→d+νe What is the half-life for the fusion of an isolated diprotium molecule in its ground state (vibrational and rotational)? Naturally big, but also naturally finite. And might be computed. An estimate...

Hello, interested, if the posibility of splitting atoms by using resonance is possible, if so, wheather or not I can use it for something else, thanks in advance.

I was watching a video explaining how microwave ovens work when I found that there is a difference between my physics textbook and online images of the electric dipole moment of the water molecule, as well as the one shown in the video. Why do they differ?

I want to ask the limits on the molecule side for single molecule fluorescence microscopy. I am writing a proposal but I lack experimental knowledge since no one in my lab have ever used one. At least how much of an absorption coefficient, with at least how much of a radiative rate is necessary...

Homework Statement Lets say i have C5H10O.. The IHD is (5x2+2-10)/2 = 1 IHD So now i use my IR chart and i determine i have ketone Now i want to find the new IHD and also figure out what other atoms i have left. So i need to subtract C5H10O by ketone and figure out the new IHD. Homework...

What I want to discuss here is what happens to the thermal velocity when an ionised gas molecule has been put into an electric field. Due to the charge (e) and potential difference (V), how much velocity has been gained by the ion can be calculated easily.eV = ½mv2 Where e is the charge of the...

The graphs of intensity versus wavelength of blackbody radiation and of number of molecules versus speed in a gas look very similar to me. Is this just a coincidence? They seem like quite different phenomena.

Homework Statement Find if a molecule is chiral or not. It is 2-chloropentane Homework Equations IF the mirror image is superimposable to the molecule it is not chiral. The Attempt at a Solution Well I wrote the structural formula in 2D and I thought it was not chiral.(bottom ) But the book...

Homework Statement My problem includes answers from previous problems that are to be used as data in this problem so I will state the previous problems and the answers but not their solutions because I have solved them and they are pretty clear to me. So, I will be only posting the solution to...

Hi guys, I've another exercise... 1. Homework Statement Determine the equilibrium internuclear distance ##R_M## of HCl molecule, knowing That some contiguous lines of the rotational spectrum of 2H35Cl are observed at the wavelengths: 234.1, 186.8, 156.4, 134.1, 117, 5 ##\mu m##. If the...

Question :- The critical volume of a gas is 0.072 L mol-1. What will be the radius of the molecule in cm ? Answer in the book :- ##V_c = 3b \implies b = 0.024 L mol## ##\therefore## for every molecule ##b = {24 \text{cm}^3\over 6 \times 10^{23}} = 4 \times 10^{-23}\text{cm}^3## per...

In the hydrogen molecule ion, one electron is responsible for the covalent bond between the atoms. But is it possible for one single elctron to create two bonds or more? What happens if we solve the Shrödinger equation for 3 protons and 1 electron?

I read a paper on how a magnetic field of 4 T was used to break the van der Waals forces of an HeO molecule with a binding energy of 11.2 cm-1. I'll put the link to my original post below. Can someone tell me how this energy was measured? Your assistance is greatly appreciated...

Homework Statement Homework Equations none The Attempt at a Solution Here is my attempted answer, can someone please tell me if I did this correctly, thank you :) 22. Final electron receptor molecule involved in aerobic respiration: * the electron transport chain relies on oxygen to keep...

If a polarised molecule, e.g NH3 or H20 (Vapour molecule) or Butane is between two plates, of opposite charge, would the charges serve to trap the molecule between the plates?

Hi, Hoping I could get some help on this one. How would I know what causes bond angles to deviate from the ideal values? I greatly appreciate any help and advice on this. Thanks