Molecule Definition and 439 Threads

A molecule of hydrogen. We assume that the only possible states of its two electrons (indistinguishable) are |A\uparrow\rangle, |A\downarrow\rangle, |B\uparrow\rangle and |B\downarrow\rangle (A=1s-orbital at atom A, B=1s-orbital at atom B). Formulate the 6 basis functions using the four...

Homework Statement The Hamiltonian for a rigid diatomic molecule is H_0 = {L^2 \over {2I}} where I is the moment of inertia of the molecule. (a) What are the lowest four energy states of this system? (b) An external electric field is applied, leading to a perturbation H_1 = ED\cos\theta...

Homework Statement [PLAIN]"Penicillin"[/URL] From the structure of penicillin above, would you expect it to be acidic, neutral or basic? Explain your answer as fully as you can. Homework Equations The Attempt at a Solution I think it would be acidic because of the -COOH. The -NH- can be...

Homework Statement A mass of 0.736 kg of molecular oxygen is contained in a cylinder at a pressure of 1.0 × 105 Pa and a temperature of 1°C. What volume does the gas occupy? Homework Equations PV=nRT V=nRT/P The Attempt at a Solution n=(.736)(1000)/16 = 46 V =...

I am currently undergoing a project for my undergraduate course in Quantum Physics on electron tunneling in the H_2^+ ion. Essentially, I am trying to model this situation in Fortran based on the variables that the user supplies (For example, the energy levels of the atoms, the separation...

Problem 10-58a: The equilibrium separation between the nuclei of the nitrogen molecule (N2) is 0.190 nm and the mass of each nitrogen nucleus is 14.0 u, where u = 1.66E-27 kg. For rotational energies, the total energy is due to rotational kinetic energy. Approximate the nitrogen molecule as a...

Homework Statement A molecule of DNA lies along a straight line. It is 1.12 μm long. The ends of the molecule become singly ionized; negative on one end, positive on the other. The helical molecule acts as a spring and compresses .4% upon becoming charged. The Coulomb constant is 8.99 X...

I know what an exited atom is : any of it's electron is elevated from the ground state. But I can't really figure out what is an excited molecule (e.g diene of polyene)... I have read molecules like diene or polyene can be excited and they absorb light wave for this as atoms do to send some of...

Here are some examples of wavefunction visualisations: http://upload.wikimedia.org/wikipedia/commons/c/cf/HAtomOrbitals.png I need the wavefunctions of the H2 molecule at 0 K, ie what the orbitals look like, whether they change with time, etc. Does anyone know the equations? Does...

Homework Statement The atmosphere is composed primarily of nitrogen N[SIZE="1"]2 (78%), and oxygen O[SIZE="1"]2 (21%). Find the rms speed of N2 and O2 at 293K Homework Equations Vrms=\sqrt{}((3RT)/M) The Attempt at a Solution V[SIZE="1"]rms, O2=\sqrt{}((3*8.31J*293K)/(32g/mol))...

[SOLVED] Electrostatic Force Homework Statement The dipole moment of the water molecule H2O is 6.17x10^-30 Cm. Consider a water molecule located at the origin whose dipole moment p_vec points in the positive x direction. A chlorine ion (Cl-), of charge -1.60x10^-19 C, is located at...

A stupid question: when we buy gas at the gas station, what is the molecule that makes up the gasoline? (I know there are additives so strictly speaking there is not a single type of molecule but I am wondering about the main constituent). Thanks

Homework Statement 2.0 moles of nitrogen (N2) gas are placed in a container whose volume is 8.4 10-3 m3. The pressure of the gas is 4.7 105 Pa. What is the average translational kinetic energy of a nitrogen molecule? average KEN2 = WebAssign will check your answer for the correct number...

"Size" of a DNA molecule? Sorry for such a beginner's question in an advanced profile forum: In basic school we were taught that a molecule of a substance is "the smallest structure which still retains all the properties of that substance. If you divide it any further, (at least some of) its...

The mass of a gas molecule can be computed from its specific heat at constant volume c_v (note this is NOT C_v) Take c_v=0.075\frac{cal}{g*C} for argon and calculate (a) the mass of an argon atom and (b) the molar mass of argon. I just finshed the chapter on Kinetic Theory of gases, but...

[SOLVED] conservation of energy Homework Statement From what height must an oxygen molecule fall in a vacuum so that its kinetic energy at the bottom equals the average energy of an oxygen molecule at 200 K? Homework Equations conservation of energy Eavg=3/2KbT Epot=mgh The...

http://img176.imagevenue.com/img.php?image=24632_help-please_122_195lo.JPG" How is the hybridization on B (a nitrogen atom - refer to pic) sp3? I only see 2 bonds? how else can i complete an octet? Could someone explain the answers to me please..i have a day remaining before my exam..im...

Given the redshift z of a galaxy, how can one measure the temperature of a molecule in that Galaxy? ( Assuming it is heated only by the CBR) ?

Homework Statement Consider an electron of a linear triatomic molecule formed by three equidistant atoms. We use |\phi_A>, |\phi_B>, |\phi_C> to denote three orthonormal staes of this electron, corresponding respectively to three wave functions localized about the nuclei of atoms A, B and C...

Hi, I have to determine the spring constant for a diatomic molecule. I have the frequency in cm^-1 which is 1395. I know the relation between the angular frequency and spring constant so I use the following relation: omega = 2*pi*c*v = sqrt(k/mu) so I isolate for k = mu*(2*pi*c*v)^2 mu...

Well, I did the problem. The problem is I KNOW my answer is wrong. Anybody have any idea why? (This is what I've worked out with my friend). Homework Statement Imagine a sphere of radius a filled with negative charge of uniform density, the total charge being equivalent to that of two...

ckg733 the so-called "anti-aging molecule" - how to control aging? I've heard ckg733 be called the "anti-aging molecule" and apparently it can reverse aging of cells? Could this be used to reverse/stop the aging of an organism? I mean if you can control the age etc of every cell you could use...

what happens to gas dipole molecule when electric field E is turn on ? a) is going to rotate to lined up with vector E and stay like that ? b) is going to oscilate, like pendulum, pointing on average toward E ? c) none of the above. d) is every collision going to flip molecule unpredictible...

Apparently physicists have been able to synthesize a molecule that contains two positronium atoms, an exotic form of atom that contains both positrons and electrons in its outer shell. They were able to monitor the properties of the molecule by the gamma rays let off after annihilation of the...

Hi. In my chemistry book, one of the questions was to name the given organic molecule. What was given was a benzene ring with a single -OH functional group attached. Immediately, i recognized it as phenol, but i also said its conventional name was benzenol. When i turned to the answers...

[SOLVED] Symmetrical Group of a molecule I'm trying to study PCl5, it have a bi-pyramidal shape, with The P atom at the center. I was able to find out the group it's D3h. 1)To what irreducible representations does The "p" orbital of Phosphor ( P ) and the five "1s" orbitals of Chloride belongs...

to whom may read this, i was desperately looking for a chemistry computer program which allows me to draw organic molecules, methane, trans-1,2-dichloroethene, cyclopentene, etc. with the bonds in them. Here is an example of what i would like the program to draw...

Hi, I am calculating the spectra of a small molecule - benzen with nitrogen group attach. I have some experimental data of the molecule IR and raman. I use DFT B3LYP with TVZ as basis set when I compare the modes and are a lot of differences between the two. 1. Would it help to increase...

This molecule has been immortalized in a sculpture on the boardwalk of the city of Halifax, NS. Wondering if anyone recognizes it. I see it has a carbon backbone and a benzene ring, but I don't know much else. I'm afraid that, other than the arrangements and bonds, there's no indication...

Homework Statement A photon of a given wavelength "lambda" collides with a hydrogen molecule that's initially at rest (photon is absorbed by H2). Assuming absorption event conserves momentum, find velocity and translational energy of H2 after the event. Homework Equations momentum of...

I made this subatomic particle simulator, but I haven't accurately placed the atoms in each molecule yet, you may be interested...enjoy! http://www.winggamepak.com/stuff/atombuilder.exe Here's a picture of it: http://www.winggamepak.com/stuff/atombuilder.jpg plus there are other...

Is a diamond a single molecule?

Homework Statement A space vehicle returning from the Moon enters Earth’s atmosphere at a speed of about 4.9E4 km/h. Molecules (assum nitrogen) striking the nose of the vehicle with this speed correspond to what temperature? Homework Equations KE=0.5mv^2=kT k: constant The Attempt...

Homework Statement The covalent bond between the two protons in the H2 molecule can be modeled by a harmonic spring with a spring constant k = 1100 N/m. a. What is the zero point energy of the H2 molecule as a harmonic oscillator? b. What is the energy of the first excited state...

b) Calculate the matrix which represents the Hamiltonian H= 1{(L)^2}/2I + Alpha*(L^z) H = part A + part B where alpha is a constant and so is I and also L^2 = Lx^2 + Ly^2 + Lz^2 (1) heres what i have done. i have calculated L^2 From adding matrices from 1 and it...

Homework Statement How many pi bonds are in the molecule C12H18? Homework Equations I have in my notes the formula (6nPi+2-total # of electrons)/2. The Attempt at a Solution Unfortunately I can't find an explination for this formula in the book and I don't remember what was...

Molecules are optically active when they react differently to left or right circularly polarized light. This is because they have a screw-oriented structure which is itself either left-handed or right-handed, making propagation preferential for one polarisation, rather than for the other...

For a molecule of water, I understand that there are 6 degrees of freedom for each of the three atoms within it; 3 translational and 3 due to the potential energy of the bonds. Is this at all affected when the water goes from solid to liquid or gas?

I understand that for H20 in solid form, each atom within the molecule has 6 degrees of freedom; 3 translational and 3 due to potential energy from bonds. Does the number of degrees of freedom change when water changes phase to a vapor?

Net Force in a DNA molecule?? Homework Statement The two strands of the helix-shaped DNA molecule are held together by electrostatic forces as shown in Fig. 16-44. Assume that the net average charge (due to electron sharing) indicated on H and N atoms is 0.2e and on the indicated C and O...

Homework Statement A water molecule is a permanent dipole with a dipole moment p = qs. There is a water molecule in the air a very short distance x from the midpoint of a long rod of length L and uniform charge +Q. The axis of the rod is perpendicular to the rod. Note that s << x << L...

Homework Statement The question can be found on this link. It is the last question, the one with the DNA molecules. Prof said that the direction is not important, he is just looking for a magnitude. http://www.phys.uvic.ca/medphys/people/AJ/Courses/Phys216/Assignments/P216-A1-2007.pdf...

Just by looking at its Lewis structure, how could you tell whether or not a molecule could have pi bonds? Thanks in advance.

Could someone list the similarities and differences between the two? Is it correct to say that 'the set of all molecules' is a subset of 'the set of all compounds'. But the vice versa is incorrect. So a 'proper' should be placed in front of the word 'subset' above. i.e. any covalently bonded...

In my thermo text, they consider a diatomic molecule that is rotating about the axis joining the two atoms (also the axis of symetry) and make a quantum argument involving the energy levels of a rigid rotator to conclude that kT<<\Delta E for this particular degree of freedom. But isn't this...

Hi, I have a quick question. Ignoring quantum stuff, shouldn't I be able to predict the angle between the two hydrogens in a water molecule if I model the three atoms as point charges and assume that both hydrogens have a partial charge of +D and that the oxygen has a partial charge of -2D, and...

http://www.physorg.com/news75883856.html Scientists at the SUNY Downstate Medical Center found a molecule that strengthens synaptic connections. By inhibiting this molecule, they can prevent connections from being maintained and "erase" them. They claim to have erased memories in people that...

How do you calculate the distances between atoms of a given gas molecule? The reason I am asking this is so I can find the moment of inertia of certain molecules so i can determine degrees of freedom for a gas at a certain temperature. Is there an easier way to determine them?

Only 3 statements are correct. A.) Water is a compound and exist as molecules at rtp. B.) Magnesium chloride is a molecule but not a compound. C.) At rtp, nitrogen exist as diatomic molecules. D.) Rubidium Oxide is a compound but not considered a molecule. E.) Oxygen gas is classified as a...

Hi, I was wondering if something like H_2 is considered to be a molecule. I've read through some websites and I'm still not sure. It's been a long time since I did chemistry (although I should probably remember :biggrin: ) so any help would be good thanks.