Atom Definition and 999 Threads

if fuel coposition as follow : 75 wt% Tho2- 25 wt% uo2, were the U enrichment 19.5 w% ... how can i caculate the number density (Atoms/barn-cm) for the comopsition ?

Hydrogen Fusion = High energy? Where does the energy come from when a Hydrogen atom is fused? Is the energy stored in some part (proton, neutron, electron)? Thank you if someone can give me some idea about this. I guess it is about the strong nuclear force, but I'd like to know in a bit more...

The nucleus has positive charge, with negative electron shell(s) around it. The nucleus is located in the center of the electron shell. Electrical forces keep it there. Now what if we shine electromagnetic radiation (linearly polarised) onto an atom? With the E-field going "up", will the...

Hi, I'm trying to figure out the solution for the ground state of the hydrogen-atom, however it is not going well. As far as i know, you can supress the angular dependence, because the states of hydrogen (or at least some of them) are spherically harmonic. This way the schr. equation just...

Say for example we consider Helium. It has 2 neutrons and 2 protons. Based on this, and using Schodingers equation we can calculate the energy states of the various orbitals of Helium (using self consistent field approach or by completely solving the Schodingers equation using finite...

In the position representation, its true that we can use operators to represent the coulombic interaction between the proton and electron of a Hydrogen atom. I've never actually given any thought as to what the elements of such an operator would be (in matrix form of course). I know these...

Why can't every country make an 'Atom Bomb' ? Everyone knows that we require a fissionable material and an explosive. What else is required that is to be invented (rather discovered) by other countries? All comments are welcome.

Homework Statement An initial state is given: {\lvert {\psi(0)} \rangle} = \frac{1}{{\sqrt{3}}} \left( {\lvert {100} \rangle} + {\lvert {210} \rangle} + {\lvert {211} \rangle}\right) An L_z measurement is performed with outcome 0 at time t_0. What is the appropriate form for the ket...

Why their tracks after collision has an angle 90 degree? Any detail derive?

Do atoms require fuel or does the electron move about the nucleous in the some way the Earth rotates the sun? Maybe it's a stupid question but I've always wondered about this.

The Yukawa-type potential energy function for the interaction of a particular pair of neutrons in an atomic nucleus is U(r) = -(a/r)U(sub o) (e^(-r/a)) where U(sub o) = 5 x 10^(-12) J and a = 1.5 x10^(-15) m. Find the force as a function of r, then evaluate the force for r=a and r=3a. To get...

Hi, If the normalized 1D wave-function of hydrogen atom for n=1, l=0, m_l=0; \psi_{1s}(x)=\frac{1}{\sqrt{\pi} a_{0}^{3/2}}e^{-x/a_{0}} and probability distribution of wave-function, \mid\psi_{1s}(x)^2\mid so integration of rho over all x should give the number of electrons which is equal to...

I've searched google for some decent tables but couldn't find any. I'm trying to collect Normalized Spherical Harmonics Associated Legendre Polynomials Zeros of the Spherical Bessel Function Normalized Radius Function for the Hydrogen atom etc. I'm allowed a sheet with as much of these...

If the universe came from a single atom, then... The current model says the universe came from the big bang, the original point being something as small as an atom, and this atom expanded into the size of the universe in which we see now. If this is true, then wouldn't it mean every atom in...

Find <nlm|(1/R)|nlm> for the hydrogen atom (nlm = 211), R is just the radial position Operator (X2 + Y2 + Z2)½.

Would someone tell me some website where I can find the relativistic treatment of the hydrogen atom using Dirac's Equation? I am not trying the find the method which uses Schrodinger's equation and adds as perturbations fine and hyperfine structures? Thank you. So far i have not find anything...

What quantities appear in both the Schrodinger approach and the original Bohr theory of a hydrogen atom? Also, in what ways do the two approaches differ? I'm not sure which quantities appear in both approaches. My guess would be that it has something to do with the energy levels and angular...

Can we or have we made an atom of neutrons?

I'm using the TURBOMOLE program to do some basic HF calculations. They all went fine except for the single oxygen atom. After doing an extended huckel theory guess to begin with, it recommended these occupations (d2h symmetry). That looks fine to me. The top two orbitals (4 and 5) are singly...

Homework Statement Assume that the density of positive charge in any Thomson atom is the same as for the hydrogen atom. find the radius R of a Thomson atom of atomic number Z in terms of the radius Rh of the hydrogen atom. Homework Equations The Attempt at a Solution I don't...

There are two cases introduced in the lecture notes, depending on strength of spin-orbital coupling in individual electrons, since V_{SL} \propto Z^{4}. 1) jj coupling, which is valid for large-Z atoms, where spin-orbital coupling > electrostatic replusion between electrons 2) L-S coupling or...

A hydrogen atom is in the state \psi=Ar^2e^{-r/a}cos(\theta). I need to find lowest energy state and etc. Obviously normalize to find A, but I'm not seeing the obvious linear combination of wave functions; and I really don't think my instructor wants me to do several inner products (plus...

Homework Statement What type of hybridization occurs in the orbitals of a carbon atom participating in a triple bond with another carbon atom? The Attempt at a Solution I honestly thought it would be sp3 but it turns out to be sp. Can someone explain this to me? Thanks!

Here comes a pretty hard question, which not even my QM teacher has been able to answer. When we think about one hydrogen atom, and put it in an electric field along the z-axis \bar E = \bar e_z E. Then the potential for a hydrogen atom will look like this: U = -\frac{e^2}{4\pi \epsilon_0...

Hello, I don't know if this is the right place to post.. this is a self study question from Levine, it is told that is important but i have no clue in solving it .. The Balmer series corresponds to a set of emissions involving the electron in a hydrogen atom relaxing from a high energy...

Homework Statement The normalized wave-function corresponding to the ground state hydrogen atom has the form \Psi _0 = \frac{1}{\sqrt \pi} \cdot \frac{e^{-r/a_0}}{a_0 ^{3/2}} where a_0 is Bohr's radius. 1)Graph the density of probability to find the electron in a spherical edge between r and...

Orbital Angular momentum quantum number of an electron in its ground state - s - state is zero, l = 0. That means in S - state atom do not have orbital angular momentum. If it is not, then is electron stop orbiting round the nucleus? How to explain this aspect? Or wether we have to abndon the...

The 1s radial function of the wave function of H atom is: R10=2 a-3/2e-r/a ,where a = 5.29*10-11 meter but substituting a with its value,we will get R10 = 5.2*1015 *e(-1.89036*1010 r) and that is impossible if r=a and R(r)=1.9*1015 where is the problem ? What's more, the unit...

I'm studying particle physics now and am confused with all these terminologies.

Homework Statement Order each of the following sets of five atoms and ions according to decreasing size. (i.e. "1" largest and "5" smallest) N, Br-, Cs, P, Mg2+ Homework Equations When an atom loses electrons (becomes more +), its size decreases. Conversely, when an atom gains...

The ground state electron configuration of Carbon atom is 1s^{2}2s^{2}2p^{2} For the electrons, 1s^{2}2s^{2}, L=0, S=0 So only consider electrons of 2p^{2}, and s_{1}=s_{2}=1/2 ---> S=0,1 l_{1}=l_{2}=1 ---> L=0,1,2 For S=0, L=0; J=0, so we have ^{1}S_{0} For S=0, L=1; J=1, so...

Homework Statement A Hydrogen atom is initially in its ground state and then subject to a pulsed electric field E(t)=E_{0}\delta(t) along the z direction. We neglect all fine-structure and hyperfine-structure corrections. Homework Equations 1. It is important to use selection rules to avoid...

think that all the mass of the atom are concentrate in nucleus and the shape of the nucleus is like a ball with radius =1.5*10^5. IF the mass of the carbon atom = 2.0*10^23. what is the density of the carbon atom? the volume of the planet Earth=4/3pie*r^3 i just want to say that...

Looking for ideas that allow me to create Methane ( CH4 ) from gaseous hydrogen. This requires bonding one carbon atom to four hydrogen atoms, which should be simple enough, but there needs to be a minimum explosive danger. I know there are appliances to go the other way, but don't have the...

Homework Statement What is the mean value of the momentum of an electron of a hydrogen atom in its ground state? Derive this mean value of the momentum from the kinetic energy of the electron. Homework Equations <p> = integral from -infinity to infinity (p*|psi|^2) dx p^2/2m = KE...

Briefly,the forces between two atoms arise from nuclear and electron-cloud repulsions, and nuclear to electron-cloud attraction. But why does the repulsion vary with respect to distance, without following the inverse square law? Should not electrostatic charges follow the inverse square law...

Homework Statement According to Bohr's atomic model, 1)Determine the allowed radius of the orbit of the electrons. Calculate the radius of the first orbit for the hydrogen atom. 2)Show that the energy of the electron is quantized. Calculate the energy corresponding to an electron on the first...

Are there any ionizing solutions for the hydrogen atom problem, where the electron breaks away from the proton?

Homework Statement 1 The density of copper is 8930 kg m-3, its mass number is 63.55 and its atomic number is 29. a) Calculate the mass of a copper atom in kg. b) How may electrons and protons does a copper atom have? c) Estimate the diameter of a copper atom...

Homework Statement During my calculation of hydrogen atom perturbation, I need to integral below in cartesian coordinate. It is given that below integral can be transformed. Homework Equations Anyone could help to see what will the transformed integral in polar coordinate if the...

Homework Statement revered members, one limitation of bohr atom model is that it could not account for distribution and arrangement of electrons. i could not understand this statement, that is, according to bohr , electrons revolve around the nucleus in circular orbits and the necessary...

Homework Statement A hydrogen atom in the n = 2 state absorbs a photon with wavelength 380 nm. Q1. Find the change in the atom’s total energy. Q2. Find the change in the atom’s potential energy Q3. Find the change in the orbiting electron’s kinetic energy. Homework Equations...

Homework Statement The electrons of the uranium atom can be approximated as a uniform density sphere with radius 7.4 x 10-13 cm. The nucleus is a point at the center with a charge of +92e, and there are 92 electrons. a. Calculate the electric potential and electric field at the surface...

Homework Statement A hydrogen atom is in a state with energy -0.278 eV. Homework Equations L = nh' The Attempt at a Solution The answer book says to do E_n = (-13.6 eV)/n^2 but I can't find this equation in our book. Is the 13.6 a significant number or just a different number...

here are the problems that I need help with: http://imgur.com/a/fERMC/1 I am afraid that I know not much information about the questions. Sadly, I am enrolled in a poorly written Physics class online. I am not looking for the answers, but just how to go about finding them. The book never...

Homework Statement Substitute an electron in a neutral hydrogen atom with a muon. a) calculate the Bohr radius of the ground state for this myonic atom of atom. The answer must be right to at least 2 significant digits. b) Calculate the fraction of the myon that is located inside the proton...

Hi guys, I need to write down the positions of all the atom in LaFeAsO unit cell: Figure caption: "The quaternary equiatomic ZrCuSiAs-type structure is very simple, with only eight atoms in the tetragonal cell. The dashed lines represent a unit cell." I also have these informations...

Homework Statement Calculate the expected value for r^2 for the 2s wavefunction of the hydrogen atom (only the radial part of the function is needed for l=0). If you choose to solve this problem graphically, plot or sketch the function you integrate. Homework Equations...

Hi! I am writting my labbraport on electronspektrum for natrium atom. Here is my electronic transitions but the teacher says that there are some transitions missing...have no clue which ones they might be...can someone explain to me what is he talking about? which are the missing electronical...

Does it have to do with the strong nuclear force holding the atoms together being released?