Molecules Definition and 543 Threads

I would be most grateful for some tips of interactive software, which shows the hybridized atomic orbitals overlapping in the molecule (I don't mean resulting molecular orbitals but atomic orbitals of which overlapping forms MO). And does this works also in Mathematica?

Homework Statement What are the number of different bond angles for the isomer of F_{3}PCl_{2} with each chlorine equatorial? What about for the isomer of BrPF_{4} with the bromine axial? According to the key the the first molecule has 5 unique bond angles. Homework Equations Trigonal...

Homework Statement An ideal gas is kept in a container of constant volume. The pressure of the gas is also kept constant. The number of molecules in the gas is doubled. If the initial rms speed is 1300m/s, what is the final rms speed? Homework Equations Vrms=sqrt[(3kT)/m] PV=NkT...

Homework Statement A container of volume 10−3 m3 has a pressure of 10−7 mbar. Surrounded by air at 1 bar and 290 K, how long does it take the pressure inside to rise to 10−6 mbar when air effuses through a small hole of area 10−17 m2? Homework Equations The Attempt at a Solution Flux ø =...

Hi, assuming I have the potential for a diatomic molecule in the groundstate i=o and excited state i=1 V_i( r ) = D( 1 − exp[ −β ( r − r_i)] )^2+ C_i Using collisional excitation with fast electrons. What is the vibrational quantum number of the state the molecule will most likely be...

I read in my Chemistry workbook that: "At higher temperatures, vapour pressure increases as more energy is provided to the liquid molecules, allowing them to escape into the gas phase." At the boiling point, all energy is gone into breaking bonds and to convert liquid phase molecules into...

Does the strong nuclear force and the electromagnetic force plat into it at all, as in their role in holding atoms together?

I have two files with atomic coordinates for the same generated strucutre (cycle made of eight sulphur atoms), but produced by two different progams (so that output files have different coordinates supposedly connected by translation/rotation). Is there some kind of software to compare the two...

Do molecules have intrinsic magnetic fields to them? Let's say you have a water molecule H20. Would the oxygen have a field due to the orientation of it's electrons, and possibly the hydrogens fields act to reduce that field? I'm just curious.

Homework Statement A scuba tank has a volume of 2800cm3. For very deep dives, the tank is lled with 50% (by volume) pure oxygen (O2) and 50% pure helium (He). The molar mass of helium is 4 g mol/1, and for oxygen is 32 g mol/1. How many molecules are there of each type in the tank if it is...

Homework Statement Estimate the bond energy between two water molcules (liquid) in the following way A: From the density of water and its molecular weight calculate the average distance between the molecules B:hence show that there are 10^19 molcules per m^2 of surace C:from the...

Estimate the probability that in a room of volume V, all the N molecules of air are found in volume \frac{3V}{4} and none at all in the reaining volume V/4 My take to the solution is Pr of finding N molecules in \frac{3V}{4} : \frac{N}{3V/4}= \frac{4N}{3V} Pr finding none in V/4...

Today in 9th grade ADV Biology, we learned about how the two Hydrogen atoms in a Water molecule are relatively positive compared to the Oxygen atom. This is because the Oxygen's pull on Hydrogen's electron is greater than the Hydrogen's, or that its Electronegativity is greater. This unequal...

I have read that the structure of almost all organic molecules can be represented visually as Planar Graphs, i.e. 2-dimensional lattice-like structures consisting of nodes (points) connected by lines in which no lines cross. From the perspective of Physical Chemistry, does anybody know why this...

I have read that relaxation of a rotational or vibrational mode in gases occurs through collisions of molecules , transferring energy of an excited vibrational mode into heat. But isn't it possible that an excited vibrational mode in molecules relaxes directly by emission of radiation...? I...

Given that molecules, atoms, protons, and neutrons are overwhelmingly space (i assume quarks and electrons are more than just fields), when an object reaches relativistic speeds, is length contraction the result of a decrease in the geometric space within the molecules, or is it a decrease in...

Homework Statement Some gas is heated in a sealed container. How do the average distance between the gas molecules, and the frequency of the molecules' collision with the walls, change when the container (A) has a fixed volume, and (B) is allowed to expand outwards? The attempt...

Hi guys, I hope you don't mind me posting here, I am doing some research into atoms, molecules and microscopes. I have no knowledge of physics, the quantum world or microscopy so if my questions seem silly, please look past that and help me. Thank you I have two questions. Is there a way...

Homework Statement Show how you would find the average distance between gas molecules at a specific volume, pressure and temp? Given; Pressure=P (torr) Temp=T (Kelvin) n=number of mol N=number of molecules Volume=V (cm)^3 Homework Equations pv=nRT N=n*(NA)...

Are there not dipole-dipole interactions between CHBr3, CH3Br, CH3Cl, and CHCl3? Assume they are all separate pure substances. My professor today said that the only intermolecular forces present were dispersion forces. Are the dipole attractions negligible due to fact they are too weak?

Is it true that in general, larger molecules will have smaller HOMO-LUMO gaps? In this case consider that we are comparing long vs short saturated molecules, and long vs. short conjugated molecules.

How do I write a full Schrodinger equation, pre-approximation, for a mixture? Let's say 75% H2 and 25% He by number of particles. I already know the form and very basic applications of the Schrodinger equation and the Hamiltonian. What I want to know is, the specifics, such as how to specify...

Hello fellow physics lovers, I wish to predict the behaviour of a organic molecule under an electric field (High Voltage). I wish to know how much E-field can this molecules withstand before being fragmented. Can anyone point toward a freeware than might compute such a field? It is...

how does non polar solute dissolve in non polar solvent?

What is the general method for finding symmetry in molecules which would allow you to find which nuclei are equivalent in an NMR spectrum? I know it sounds vague but it seems inevitable. Any good guides on the Internet would be great. My main issue is with larger molecules whose structures are...

Homework Statement Look at the image please. The image shows 3 pairs of compounds. Explain why the first two are not chiral but the last one is chiral. Homework Equations Ar means Aromatic ring Aquirais means aquiral Quirais means chiral The Attempt at a Solution...

how does dehydration occur in organic molecules(extracting of OH and H radicals)

What is the equivalent weight of ozone molecule? I mean how can I find out the equivalent weight of molecules? Is it same as the equivalent weight of element? For example, FeCl3 ,what will be the equivalent weight of chlorine ?

Homework Statement A sample of oxygen gas with molar mass 32 g/mol contains 5.0 moles and is at a temperature of 500 K. How many moles of the gas have speeds between 375 m/s and 380 m/s? Homework Equations Maxwell Boltzmann Distribution: f(v) = 4\pi[\frac{M}{2pi RT}]^(3/2) * v^2 *...

The kinetic theory states that the gas molecules are randomly colliding with each other and with the wall of the container with high speed.The area of each molecule is very less and as they are moving with high speed,they exert great force. since the pressure is force/area , the pressure should...

Hello, The formula for average kinetic energy of molecule is: k=3/2KT. Can anyone please explain the derivation without using calculus? Thanks, -- Shounak

When we use Boyle's Law it means that as pressure increases the volume of the container would decrease. In my notes they stated that if I were to halve the volume there would be two times the number of collisions per second which implies that the force exerted is doubled. But why is this so? I...

We can simulate physical movements of atoms and molecules and how they interact with many software like ascalaph or abalone. But can we one day simulate complex interaction of molecules like the interactions that happens inside a simple organism like a simple bacteria? And going further, can...

When making the Morse Potential graphs of diatomic molecules going through a transition, the excited state sometimes has a different equilibrium bond length. A visual example is here: http://en.wikipedia.org/wiki/File:Franck-Condon-diagram.png I was wondering how the average bond length of...

Many times, I find it hard to draw correct Lewis structure of molecules with nitrogen. For instance: the Lewis structure of H2CNN. I thought it should be double bond between C and N and single bond between N and N, like this: But actually it's not. I have done many problems like this wrong...

I'm way outside my realm of knowledge here so perhaps I need some help polishing my question or the concepts behind it. Thank you for your patience. Does the orientation of circularly polarized light (CPL) as a reaction mechanism influence the chirality of the molecule in a general manner...

Can a strong magnetic field move water molecules because it is a polar molecule. How strong does the field need to be?

Homework Statement When we have a liquid, there are Van der Waals forces of attraction in between each molecule. Hence, the negatively charged electron cloud would be attracted to the positive nucleus of the neighboring molecule. However, there seems to be a gap in between the molecule (least...

By changing the arrangement of electrons in a molecule's energy levels (without adding or removing any electrons), can the molecule become destabilized or come apart? An example or two would really help. Thanks, Jake

Homework Statement Let a box of height h be filled with classical ideal gas molecules of mass m in a constant gravitational filed g. As will be shown later, the distribution molecular height z obeys: f(z) = C exp (-mgz/KT) Where C is the normalization constant a) find the average height...

Author: Wolfgang Demtröder Title: Atoms, Molecules and Photons: An Introduction Amazon Link: https://www.amazon.com/dp/3642102972/?tag=pfamazon01-20 Prerequisities: Contents:

If molecules generally move at sound speed, given they are accelerated at Mach 1, does this mean there are less arbitrary collisions? or less collisions in general and more molecules move in the direction of mach 1 speed??

Homework Statement Hi, dispersion force exists in non-polar molecules due to instantaneous dipole. In polar molecule,the intermolecular force is the sum of dipole-dipole force and dispersion force. Polar molecules have permanent dipoles,this enables the oppositely charged end of molecules...

Was just wondering whether or not it was at all possible to create "sound" from molecule interactions, and if so how would I go about it? I was going on the theory that if E=hv then a frequency is obtained when this equation is applied and as sound is theoretically a frequency (movement of...

I was solving an exercise my teacher asked us, to determinate the hibridization of the molecules. He give the molecule and I have to tell which hibridization it is. I want to know if I can do this to every molecule, I mean, are all molecules in the world hybridized? If so, why do we have to...

hi all. I'm trying to write an article about a molecular perspective on (aircraft) lift. I am guessing nitrogen does most of the lift since it's the most abundent in air. how does a nitrogen molecule stick to a steel molecule (plane's)? is there a short term electronic bond between the two...

I'm confused with this topic. However, I think I know a bit. There's something to do with the temperature and it affects the energy of the molecules. Can someone help?

What problem arises or may potentially arise if drug molecules bind to plasma cells?

Homework Statement

Thought I'd share this article w/ everyone since I found it very interesting. Imagine being able to regulate stem cells without the need for genetic manipulation or growth factors etc. Small molecules are so much easier to work with. Very interesting...