Hydrogen Definition and 1000 Threads

  1. M

    Does Helium or Hydrogen have the greater atomic radius?

    I've been looking online at multiple resources and seem to be getting conflicting answers. http://www.sciencegeek.net/tables/AtomicRadius.pdf - Where He is slightly smaller than H http://intro.chem.okstate.edu/1314F00/Lecture/Chapter7/ATRADIID.DIR_PICT0003.gif - Where H is smaller than He...
  2. Philosophaie

    Spectrum of Light from Hydrogen

    The visible spectrum of light from hydrogen displays four wavelengths, 410 nm, 434 nm, 486 nm, and 656 nm normally. Which changes when a telescope is pointed at a Galaxy that is moving away?
  3. C

    Why Does the 3s Hydrogen Wave Function Use the Polynomial (27-18σ+2σ²)?

    Hi, I am wondering why the associated Laguerre Polynomial for the 3s hydrogen wave function is (27-18σ+2σ2). My physical chemistry book tells me that the complete hydrogen wave function is given by: \Psi(r,\theta,\phi)= RnlY^{m}_{l}(\theta,\phi) and Rnl(r) uses the Laguerre polynomial...
  4. G

    Rigid, Hydrogen Based, Moored Balloon

    Hello. I've regained a certain interest in lighter-than-air-craft recently. To satisfy this interest, I wish to construct a small, rigid, unmanned, moored, hydrogen balloon within the bounds of reason. I'm most definitely not an engineer to any extent, and as such, I have many questions...
  5. A

    What is the Energy of One Hydrogen Atom?

    According to Einstein's equation, E=mc^2, I calculated the energy from one hydrogen atom to be roughly 5.01*10^-15 Newtons. I am unsure as to if this is correct. Please help me.
  6. P

    How Can We Represent Electron Wave Length in an Equation?

    I wanted to know elecrons wave length(If you can show me this in picture I will be glad and not wave function Just wave length) how can we show this in equation.(not bohr model)(The last theory(Shrödinger)) Thanks
  7. ajayguhan

    Why does platinum adsorb hydrogen

    Why does platinum adsorbs hydrogen, when platinum being one of the inert element? Is there any law which states about the adsorbent and the adsorbent gas? Why do some elements like platinum absorbs while some elements doesn't adsorb gases!? Is there a way to predict that this element or compound...
  8. Roodles01

    Total energy of Coulomb model of Hydrogen atom

    Homework Statement Hi, my question is regardng a Coulomb model of an H atom specified with Hamiltonian operator, Hhat, by spherical coordinates of energy eigenfunction ψ2,1,-1 (r,θ, ∅) =(1/ 64∏a02)1/2 r/a0 e-r/2a0 sinθ e-iθ Principal quantum numer n = 2 orbital an mom l = 1 magnetic...
  9. B

    Simultaneous observables for hydrogen

    Homework Statement Is there a state that has definite non-zero values of E, L^2 and L_xHomework Equations L^2 and L_z commute with the Hamiltonian so we can find eigenfunctions for theseThe Attempt at a Solution I would say that there is a state with simultaneous eigenfunctions of L_x,L_y,L_z...
  10. A

    Are There More Efficient Ways to Store Hydrogen for Fuel Cells?

    I've been toying around with an experimental idea for an efficient way to store hydrogen for use in hydrogen fuel cells, but recently I haven't been able to think of much more to add to it. I've thought of using cooling and pressure together to put the hydrogen to a liquid form for more...
  11. B

    Modified Coulomb model for hydrogen, minimising error

    Homework Statement The ground energy can be approximated as E_{1}^{(1)}\approx-\frac{4b^2}{a_0^2}E_R Find the largest value of b that would be consistent with the ground-state energy of a hydrogen atom that agrees with the predictions of the Coulomb model to one part in a thousand...
  12. B

    First order perturbation for hydrogen

    Homework Statement Assume that there is a deviation from Coulomb’s law at very small distances, the Coulomb potential energy between an electron and proton is given by V_{mod}(r)=\begin{cases} -\frac{e^{2}}{4\pi\varepsilon_{0}}\frac{b}{r^{2}} & 0<r\leq b\\...
  13. gauss44

    Can sulfur participate in a hydrogen bond?

    I googled it and got both answers, "yes" and "no." What I mean is: O-H-S, F-H-S, N-H-S, etc. Ex.'s of "yes": http://www.ncbi.nlm.nih.gov/pubmed/19089987 [PLAIN]http://pubs.rsc.org/en/content/artic.../ce/c0ce00760a[/URL] Ex. of "no": http://www.nature.com/nature/journal.../149218a0.html
  14. S

    What causes differences in polarity between alcohol and ketone molecules?

    What is the relationship between polarity and hydrogen bonding? I have come across several problems saying that an alcohol is more polar than a ketone because of hydrogen bonding but I don't see the relationship between these two. Intuitively, I thought ketone would be more polar because it has...
  15. G

    Wave function of bonding orbital of Hydrogen molecule

    Hi I am currently looking for the wavefunction of the bonding orbital of the hydrogen molecule. Does anybody here know how this one might look like? So, since there is no complete analytical solution for the Hydrogen atom Schrödinger equation, I am currently looking for approximations of this...
  16. S

    Do QED corrections strengthen or weaken hydrogen's binding energy?

    Binding energy equations can be derived for the main spherical orbitals of hydrogen. If derived correctly, the energies computed by the equations are negative in value, for example, the well known approximate -13.6 eV for hydrogen's spherical ground state. In QED, corrections are added to the...
  17. L

    Discussion of low cost hydrogen methods

    I would like to explore possibilities of production of really cheap hydrogen by finding a substitute for scrap aluminum in the current hydrogen on-demand known reaction: 2Al + 6H2O -> 2Al(OH)3 + 3H2 (catalyzed by specially treated carbon, carried out at 85 °C.) The above reaction is scalable...
  18. D

    Exploring Selection Rules for Hydrogen Atom

    I have a couple of questions about selection rules for the hydrogen atom. When we talk about these rules in an undergraduate context we are usually assuming LS coupling where we ignore spin orbit coupling so orbital and spin angular momentum are essentially independent. Is that correct...
  19. jfizzix

    How is the energy of an electron lost in a classical hydrogen atom?

    Consider the following. You have an electron of negative charge orbiting a proton of positive charge at some distance R (i.e. a classical hydrogen atom). I understand the hydrogen atom is unstable under classical physics because the accelerating electron loses its kinetic energy as...
  20. K

    Exploring the Energy Difference of a Hydrogen Atom in a Magnetic Field

    Homework Statement • Consider a hydrogen atom in its ground level, placed in a magnetic field of 0.7 T along the z axis. (a) What is the energy difference between the spin-up and spin-down states? (b) An experimenter wants to excite the atom from the lower to the upper state by sending in...
  21. B

    Hydrogen isotopes in palladium

    I realize that Palladium has a molecular property to hold immense amounts of hydrogen, but can Palladium also “hold” isotopes of hydrogen.
  22. A

    Why does hydrogen is taken specially in intermolecular forces?

    Though there are other atoms with less electronegativity which can form effective attraction forces,why hydrogen is taken as a speacial case?
  23. S

    Van der Waals radius of hydrogen deuteride

    Does anyone have a reference for experimental and/or estimated Van der Waals radius for the molecule hydrogen deuteride ? Symbolically, this would be a proton {(p)e-} + {(np)e-} deuterium. I would like to know how closely the two atoms can approach each other to maintain the stable state of a...
  24. U

    What ion is this? even emission lines matches lyman series of hydrogen

    Homework Statement Calculate the wavelength of the Lyman-α line (the transition from the 1st excited state to the ground state) for (a) hydrogen atoms and (b) positronium e+e-, and explain the origin of their difference. In the light emitted from a star, a pattern of emission lines is found...
  25. N

    How does a single photon heat hydrogen in space?

    How does one Photon heat one atom of Hydrogen? (One Proton, one Neutron, one Electron. If you'll allow) It looks to me that the solar energy (Photon) is captured by the field(s) between the Proton and the Neutron. It also looks to me that the Proton/Neutron field is complex and may capture...
  26. DennisN

    Hydrogen Atoms under Magnification (paper)

    (PF members Salman2 and ftr have already mentioned this in two threads, but I think it deserves it's own thread :smile:) Hydrogen Atoms under Magnification: Direct Observation of the Nodal Structure of Stark States Abstract: To describe the microscopic properties of matter, quantum...
  27. F

    The radial probability density for the hydrogen ground state

    Is there an experimental verification of the radial probability density for the hydrogen ground state given in the introductory texts. See the following link as an example. Thank you in advance. http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/hydrng.html#c1
  28. D

    What is the velocity of the hydrogen atom after absorbing the photon?

    A stationary hydrogen atom with a mass of 1.67 x10^-27 kg absorbs a photon of light with an energy of 10.2eV.What is the velocity of the hydrogen atom after absorbing the photon? This is my question: Is it true that the atom has no speed since all the energy is completely absorbed at the...
  29. M

    The Normal Zeeman Effect and Hydrogen States

    I'm studying the hydrogen atom and have this question. Apparently it can be solved without perturbation theory, however I'm having trouble justifying it. Homework Statement 2. The attempt at a solution Avoiding perturbation theory I simply get: E = E(n) - constant*(mh) where m...
  30. D

    Hydrogen bond between tetrafluoromethane and water

    Homework Statement My textbook wrote that haloalkanes are generally insoluble in water.It is because the polar C-X bonds are not polar enough to make the haloalkanes soluble in water. Consider tetrafluoromethane Difference in electronegativity between F and C = 4.0 - 2.5 = 1.5 Difference in...
  31. R

    Photon emission by an excited hydrogen atom

    Typically (in popular literature) the process of photon emission by an excited atom is considered as an instant event. But actually it is quite likely that it is a continuous process. Such processes are usually described by evolutionary differential equations (ODEs or PDEs). Assume that we...
  32. edpell

    Best way to ionized hydrogen gas?

    Hello, I want to do an experiment in hydrogen gas H2 (1 bar) and I want to simulate the maximum amount of H+. What is the best way to get the largest fraction of H+ with minimal energy input? Thanks.
  33. Q

    Acceleration operator and the electron in a hydrogen atom

    I am wondering about acceleration in quantum mechanics. Let's consider spherically symmetric potential V(r). From the Heisenberg equation of motion, one finds the time derivative of the momentum operator \dot{\hat{p}}=\frac{i}{\hbar}\left[\hat{H},\hat{p}\right] = -\nabla V, from which we can...
  34. V

    What is the <r> for a hydrogen atom in n=2, l=1, m=0 state?

    Homework Statement Hydrogen is in n=2, l=1, and m=0. Wave function is ψ(r,θ,∅)=(1/4(√2pi)ab3/2)(r/ab)(e-r/2ab)(cos(θ) Find <r> for this state. Homework Equations P(r) = 4pir2|R(r)|2 <r> is equal to the integral from 0 to ∞ of P(r)dr The Attempt at a Solution I understand...
  35. R

    The proportion of Hydrogen to limit errors in measurement.

    It is proposed to use a katharometer to mesaure the amount (about 5%) of oxygen in nitrogen, in the presence of a small amount (0.5%) hydrogen. How constant would the proportion of hydrogen have to be in order to limit errors in measurement of % oxygen to +/- 0.1%? The thermal conductivities...
  36. B

    Hydrogen Atom Shells: Inner & Outer Electron Shells?

    Do hydrogen atoms have inner and outer electron shells? I saw a diagram somewhere that showed a carbon atom with an inner and outer shell, is this proven? Are these shells magnetic or something else? Do you consider the outside of these shells as the diameter of the atom?
  37. L

    Hydrogen atom. Simple question I think.

    When you solving Sroedinger eq for hydrogen atom you get energy values ##E_n\approx \frac{1}{n^2}##. Why for some value of this energy electron don't leave atom?
  38. D

    Forming Hydrogen wave functions with real spherical harmonics

    Hi, I'm a little confused about how to apply the real spherical harmonics when building a hydrogen wave function. I'm doing a computational project, so I want to work with a wave function which is strictly real, and I'm hoping I can do so by building the orbitals using the real spherical...
  39. F

    Hydrogen atom probability of electron inside nucleus

    Homework Statement The ground state of the hydrogen atom has the wavefunction: \psi (r) = \frac{1}{\sqrt{\pi}} (\frac{1}{a_{0}})^{\frac{3}{2}} e^{-r/a_{0}}, where a_{0} = 0.53Å a) Calculate the probability that an electron will be found inside the nucleus of the hydrogen atom, which is...
  40. T

    Can Adding an Electron Change the Properties of a Hydrogen Atom?

    If you stuck 1 electron into the inner shell of a hydrogen atom, would the properties change? Thanks all, Joe.
  41. sunrah

    Statistical operator of hydrogen atom

    Homework Statement Individual hydrogen atoms have been prepared in the energy state n = 2. However, nothing is known about the remaining quantum numbers. Fine structure and all corrections can be ignored. What is the micro-canonical statistical operator. Homework Equations \hat{\rho_{mc}} =...
  42. Y

    Para / Ortho Hydrogen (H2) Spins

    Is there an intuitive way of understanding these terms? I understand the mathematics that shows why there are 3 states with proton spins aligned(orthohydrogen) and 1 with spins misaligned. However, when you count them, there are really only 2 states in which the spins are aligned (up-up and...
  43. Jadaav

    Intermolecular and intramolecular hydrogen bonding

    Intermolecular hydrogen bonding is stronger than intramolecular hydrogen bonding. But how to differentiate between an intermolecular and an intramolecular hydrogen bonding ? How can I know if there is the presence of an intermolecular or an intramolecular hydrogen bonding in a molecule ?
  44. M

    Understanding Hydrogen Selection Rules: Emission vs. Absorption and the p-Series

    Please see attachment. What are the arrow heads supposed to mean? Only emission is allowed and no absorption? I mean, selection rules allow Δl=±1. But the figure is saying otherwise. I also read in another book, that the only series observed in absorption is that to the ground state, where...
  45. P

    Why does a deuteron nucleus have spin 1? Hydrogen spin 1/2?

    I'm learning about NMR and it's been stated that deuteron has a spin 1 nucleus and so should exhibit different behavior. Why? I've heard of electrons having spin, and now protons, but I don't see why the spin of a neutron should matter since it's uncharged. I'm thinking a spin of 1 means...
  46. S

    Clarification on Liquefaction of Hydrogen Gas

    Hi there, I've been looking around on the net for some information on how Hydrogen gas is converted to liquid in industry. However, I haven't had too much success. If anyone could help me understand the basic process I would be very grateful. What I currently know is that the Hydrogen...
  47. B

    Atomic Hydrogen gas cloud to Star

    Atomic Hydrogen gas cloud to Star! what would be different about stars and their formation if interstellar medium only has atomic gas and nothing else? how would it affect stellar interior and energy production? My guess is that since atomic hydrogen is less massive than molecular...
  48. T

    Expectation values for Hydrogen

    Ok, so I'm a little confused about why <p> = 0 for Hydrogen in the ground state. If someone explain the reasoning behind this, I'd greatly appreciate it. Also, and more importantly, does that mean that <p> = 0 for Hydrogen in other states as well? If not, how would you go about finding <p>...
  49. T

    Radial postion - momentum uncertain for 2s Hydrogen

    Homework Statement I'm trying to calculate delta r * delta p for the Hydrogen atom in the 2s stateHomework Equations ψ(r) = (1/ 2√π) (1 / 2a)^(3/2) (2 - (r/a)) e^(-r/2a) where a is the bohr radiusThe Attempt at a Solution I figured out that <r> = 6a, but I'm at a loss as to how to figure out...
  50. C

    Saha equation to determine fraction of hydrogen atoms ionised

    So i have a homework question which i can't figure out. Use the saha equation to determine the fraction of hydrogen atoms that are ionised at the centre of the sun (N_II/N_tot) T=15.7x10^6K number density n=6.1x10^31 m^-3 m = mass of electron the saha equation is N_(i+1)/Ni =...
Back
Top