Hydrogen Definition and 1000 Threads

Hydrogen is the chemical element with the symbol H and atomic number 1. With a standard atomic weight of 1.008, hydrogen is the lightest element in the periodic table. Hydrogen is the most abundant chemical substance in the universe, constituting roughly 75% of all baryonic mass. Non-remnant stars are mainly composed of hydrogen in the plasma state. The most common isotope of hydrogen, termed protium (name rarely used, symbol 1H), has one proton and no neutrons.
The universal emergence of atomic hydrogen first occurred during the recombination epoch (Big Bang). At standard temperature and pressure, hydrogen is a colorless, odorless, tasteless, non-toxic, nonmetallic, highly combustible diatomic gas with the molecular formula H2. Since hydrogen readily forms covalent compounds with most nonmetallic elements, most of the hydrogen on Earth exists in molecular forms such as water or organic compounds. Hydrogen plays a particularly important role in acid–base reactions because most acid-base reactions involve the exchange of protons between soluble molecules. In ionic compounds, hydrogen can take the form of a negative charge (i.e., anion) when it is known as a hydride, or as a positively charged (i.e., cation) species denoted by the symbol H+. The hydrogen cation is written as though composed of a bare proton, but in reality, hydrogen cations in ionic compounds are always more complex. As the only neutral atom for which the Schrödinger equation can be solved analytically, study of the energetics and bonding of the hydrogen atom has played a key role in the development of quantum mechanics.
Hydrogen gas was first artificially produced in the early 16th century by the reaction of acids on metals. In 1766–81, Henry Cavendish was the first to recognize that hydrogen gas was a discrete substance, and that it produces water when burned, the property for which it was later named: in Greek, hydrogen means "water-former".
Industrial production is mainly from steam reforming natural gas, and less often from more energy-intensive methods such as the electrolysis of water. Most hydrogen is used near the site of its production, the two largest uses being fossil fuel processing (e.g., hydrocracking) and ammonia production, mostly for the fertilizer market. Hydrogen is problematic in metallurgy because it can embrittle many metals, complicating the design of pipelines and storage tanks.

View More On Wikipedia.org
  1. B

    Why do hydrogen and atom bombs have such force?

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

    Why is hydrogen the most common element in the universe?

    i understand that everything else is less as they are (in turn) made from hydrogen, but why was so much of hydrogen made in the big bang? i got a feeling because one proton and one electron is stable. (similarly, helium was produced as 2 nucleons + 2 electrons is also very stable) but I've...
  3. H

    Renewable hydrogen electrolysis system, advice needed

    Hello I'm currently in the middle of a dissertation project, a feasibility study of a tidal/hydrogen generation system. At the moment I'm getting pretty bogged down trying to model the electrolyser. I'd like it to be more detailed than simply power in*conversion efficiencies. In particular...
  4. Z

    How much pressure can be created by the decomposition of Hydrogen peroxide?

    We are a simple robotics group working in Antarctica. We have a small but nimble ROV that we launch through a hole we drill in the ice. We need to lift heavy objects off the sea floor. I want to use the decomposition of H2O2 to initiate a state change that creates the buoyancy to lift these...
  5. Z

    What is the meaning of the electron energy states in a hydrogen atom?

    You see hydrogen electron energy states labeled as 1s1/2, 2s1/2, 2p1/2 and 2p3/2. My confussion may be with understanding the definitions, but does not the 2s1/2 state imply that there are 2 electrons around as the 1st s orbital is filled. But, by definition doesn't that mean you are dealing...
  6. C

    Do photons cause electrons to accelerate in an atomic orbital?

    lets say i have a hydrogen atom and i shoot a photon at it but the photon does not have enough energy to kick the electron to the next energy level , does the electron absorb the photon and if it does what happens ?
  7. J

    Detecting hydrogen gas via IR spectroscopy

    Say I want to monitor the interface of an electrochemical cell via IR spectroscopy. If H2 gas is generated, there must be a characteristic IR signature to this event. How can I figure out what this is? Are there calculations for this? I'm sure this is in the literature somewhere, but I...
  8. E

    The stability of the hydrogen atom

    Hi there! If I want to find the eigenstates of the hydrogen atom in QM I start with the hamiltonian of a free particle in a Coulomb potential. But an electron in a coulomb potential is stable in classical mechanics too! The instability of the system comes from the fact that the electron...
  9. M

    Hydrogen Spectroscopy: 2S-2P Lamb Shift Transition Frequency

    I'm looking for the more precise value for the 2S-2P lamb shift transition frequency. I found the value 1 057 844.0(2.4) kHz in the National Institute of Standards and Technology website: http://physics.nist.gov/PhysRefData/HDEL/transfreq.html. Can someone tell me if there is a better value...
  10. A

    About The Bohr Model of the Hydrogen Atom

    Homework Statement What energy (in eV) is required to remove the remaining electron from a singly ionized helium atom, He+ (Z = 2)? (a) 3.40 eV (c) 27.2 eV (e) 76.9 eV (b) 13.6 eV (d) 54.4 eV Homework Equations Ei - Ef = hf The Attempt at a Solution Ef: the 1st level Ei...
  11. P

    Please confirm Hydrogen atom question

    Homework Statement Diagram not to scale: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Energy (J) n = 3 ----------------------------------------… - 0.24x10^-16 n = 2 ----------------------------------------… - 0.54x10^-18 n = 1...
  12. Q

    Electricity generation using hydrogen

    In fuel cells hydrogen combines with oxygen (due to a catalyst) resulting in a potential difference. Is it not possible to burn the hydrogen and use the energy from this exothermic reaction to produce electricity? Since the rate of reaction of hydrogen combustion is quite high we could keep the...
  13. D

    Which Bond is More Polar: Carbon Hydrogen or Phospohorous Hydrogen?

    I had a question in a lab about which elements are least likely to form polar covalent bonds with hydrogen. From what I understand, what governs how polar a bond is, is the electronegativity of the element. The answer said that Carbon was the one which was least likely to form the bond, but...
  14. S

    Generate Hydrogen Gas for Tethered Balloon - Cheap & Portable Solutions

    Hi All, I am currently designing a tethered balloon. The balloon is 36m3 and I was hoping to fill with hydrogen. The balloon will only be fully inflated at 400ft as I am aware of the risk of a hydrogen explosion. Unfortunately I live in Australia and 36m3 of hydrogen is USD$1800! I am...
  15. O

    Understanding Hydrogen 2p Doublet: Removing Orbital-Spin Degeneracy

    I am trying to better understand this concept. for an n=2 state, l=1 we have three values for the magnetic quantum number, -1,0,1. Now in the absence of an "external" field we still have the orbital magnetic moment.So we can say that the magnetic field that the electron craete by its orbit...
  16. T

    Photoelectric Effect of hydrogen atom

    1. The problem statement A hydrogen atom has an electron in the fundamental state. a. Show that a radiation with λ = 50 nm will ionize the atom. b. What will be the excess kinetic energy of the electron in joules? What is this question asking? Is it asking what wavelength will free...
  17. N

    Can I Pursue a Career in Hydrogen Fuel Cells?

    Hi all, I recently made my own hydrogen fuel cell and really enjoyed the process and everything I learned. I didn't know much about electronics or cells, so it was a great learning experience. In my research I found that chemical engineers made a nanometal to work as a catalyst instead of the...
  18. M

    Hydrogen peroxide as an oxidising agent

    Hi I recently did a reaction (see my last post for specifics) where hydrogen peroxide acted as an oxidising agent under basic conditions to oxidise Mn2+ ions in solution to MnO2 It did look as if some gas was liberated but hydogen peroxide only liberates oxygen when it is reduced...
  19. D

    Ground state hydrogen parallel to the double slit experiment?

    In the double slit experiment the electron can go through either slit. As long as it is not observed there is an interference pattern as the two possibilities superimpose. The common conclusion to this is that the electron goes through both slits. Is there a parallel with the ground state...
  20. B

    Hydrogen Spectral Series Question

    I do not understand the distinction between the Lyman, Balmer, Pascher series etc. I understand that you calculate the values in each series with the corresponding n' values but I don't understand the need for multiple series. Why can't you have one overarching series that covers the entire...
  21. B

    How did the Hydrogen Atoms formed from Energy ?

    Hi all,well my first questions, such a huge community, thanks to the admin/staffs for this making this forum :) How did the Hydrogen Atoms formed from the energy in the early universe ? like our DNA determines how we are built (just a sample approach), was there in the energy any...
  22. M

    Reaction of Manganese and hydrogen peroxide

    Hi In a recent lab I reacted Mn2+ ions with NaOH. The Mn 2+ ions exist in this equilibria [Mn(H20)6]2+ + H20 <=> [Mn(H20)5OH]+ + H30+ Addition of NaOH ions shift this equilibria to the left (by removing protons) until Mn(OH)2 is precipitated Hydrogen peroxide is then added and some...
  23. C

    Hydrogen Spectrum: Blue Line w/ 434nm Wavelength

    Homework Statement The hydrogen spectrum contains a blue line with a wavelength of 434nm. Photons of blue light are emitted when hydrogen's electron drops from the fifth energy level to a lower energy level. What is the lower energy level? Homework Equations 1/wavelength = R [ 1/n2^2 -...
  24. K

    Finding wavelength of hydrogen atom when changing energy states

    Homework Statement Find the wavelength of the radiation emitted when a hydrogen atom makes a transition from the n = 6 to the n = 3 state. Give answer in µm. Homework Equations z^2 / n^2 x 13.6ev delta E = E2 - E1 = hv The Attempt at a...
  25. W

    How to Find Eigenfunctions of Lx for a Hydrogen Atom in a Specific State?

    The system is at the state of Φ=aY_11+bY_20 (a^2+b^2=1),please find the possible eigenfunctions of Lx and the relevant possibilities? My solution: I have attempted to use the matrix mechanics to work out the exercise,but I should work out a 8-order matrix. Firstly I use the Fmn=〈m︳F|n〉to...
  26. H

    Exploring the Hydrogen Atom: 1s Electron Distance & Quantization

    1. The most probable point a 1s electron will be found in the hydrogen atom is r = 0. 2. The most probable distance that a 1s electron will be found in the hydrogen atom is r = 0. 3. For a hydrogen atom with l (lower case L) = 0, Ψ is independent of the angles Θ and Φ. 4. For a hydrogen atom...
  27. C

    Average Potential Energy of a hydrogen 1s electron

    I can't find any reference to this in my notes. The problem is to calculate the average potential energy of a hydrogen 1s electron. The operator is V=e2 /4piE0r
  28. C

    Controlling Electron Orbitals: The Key to Creating a Hydrogen Atom?

    how do i make a hydrogen atom , if i shoot an electron by a proton will it start to orbit the proton , what dictates whether it will orbit or not .
  29. V

    Hydrogen Atom and an Infinte Square Well

    Homework Statement Comparing the hydrogen atom orbitals to an infinite square well. a.) For the hydrogen atom, what is the energy difference between the ground state and the next energy level? b.) Now 'tune' an infinite square well holding a single electron so that it has the same energy...
  30. I

    Thinking about electronic collisions with hydrogen.

    This seems like such a simple question and I feel like an idiot asking it, but here goes: If we have a hydrogen atom (not molecule) at "rest" and we shoot an electron at it with a certain known energy, what could happen? To me, it seems as though there are two distinct outcomes; either the...
  31. S

    Calculating Expectation Value of Angular Momentum Squared for Hydrogen Atom

    Homework Statement Consider a hydrogen atom whose wave function at time t=0 is the following superposition of normalised energy eigenfunctions: Ψ(r,t=0)=1/3 [2ϕ100(r) -2ϕ321(r) -ϕ430(r) ] What is the expectation value of the angular momentum squared? Homework Equations I know...
  32. C

    Relativistic Mechanics of Hydrogen Like S Orbials at high Z

    In the middle of studying for my matrix mechanics/atomic orbial/diatomic bonding final and something has been itching at my buttcrack for a while. Above Z=20 or so the lower orbitals (that don't actually exist so I've come to find out) have to be calculated with relativistic QM because the...
  33. T

    How is Energy Released from Breaking Bonds in Liquid Hydrogen?

    When working with liquid hydrogen or LH2 as a fuel how can you determine how much energy will be released when you break the bond. And an off topic question here can you determine how much force that energy that will produce.
  34. B

    Fraction of Hydrogen Atoms in First Excited State

    Homework Statement 1. Homework Statement The temperature of the surface of a certain star is 8000 K. Most hydrogen atoms at the surface of the star are in the electronic ground state. What is the approximate fraction of the hydrogen atoms that are in the first excited state (and therefore...
  35. R

    Normalization of Hydrogen wavefunction

    Homework Statement Show that the (1 0 0) and (2 0 0) wave functions of hydrogen atom are properly normalized. Homework Equations I know that (n l ml): (100) = (2/a^(3/2)) exp^ (-r/a) (200) = (1/((2a)^(3/2))*(2-r/a) exp^(-r/2a) The Attempt at a Solution I started with...
  36. A

    Troubleshooting Hydrogen Discharge Tubes: Potential Causes for Emission Stoppage

    Hi, I experimented with a hydrogen tube and after some time the emission stopped.could it be because all hydrogen atoms became completely ionized?
  37. G

    Volume Effect of the Proton in Hydrogen Atom

    This Prob is from Shankar, 17.2.3 "we assumed that the proton is a point charge e. If the proton is a uniformly dense charge distribution of radius R, the interaction is modified as V(r)= -2(e)^2/(2R) + (er)^2/(2(R)^3) r<R = -e^2/r r>R Calculate 1st Order shift in the ground-state...
  38. D

    Is there any other form of energy releasing fusion besides hydrogen

    Is there any other form of energy releasing fusion besides hydrogen fusion?
  39. D

    Excited hydrogen atom and wavelength

    i have been working on this question for quite a while. no help on google, or my textbook at all. A hydrogen atom in its ground state is excited to the n=5 level. It then makes a transition directly to the n=2 level before returning to the ground state. A) What are the wavelengths of the...
  40. FeDeX_LaTeX

    Positive Hydrogen Ion = Proton?

    Hello; Is this statement true? A hydrogen positive ion would have no electrons, and pure hydrogen itself has no neutrons. Therefore, would it simply be a proton? Thanks.
  41. B

    Newtons from Bouyancy underwater comparing helium, oxygen, and hydrogen

    I have an under water application where I need the maximum amount of buoyancy with a limit to the volume i can use for a lifting device. My question is how much more Newtons would be exerted for helium instead of oxygen, or hydrogen instead of oxygen underwater? What is the percentage...
  42. X

    A plane wave vs the bound state of Hydrogen atom: orthogonal?

    These days I met one problem and asked a professor for help. But I can not understand his answer. Can you help me explain his answer? My question is that whether we can assume that a plane wave is orthogonal to the bound state of Hydrogen atom when t->\infty? Professor answers...
  43. F

    How to Derive the Hydrogen Atom Hamiltonian in Spherical Coordinates?

    The Hamiltonian for a Hydrogen atom in Cartesian Coordinates (is this right?): \hat{H} = - \frac{\bar{h}^2}{2m_p}\nabla ^2_p - \frac{\bar{h}^2}{2m_e}\nabla ^2_e - \frac{e^2}{4\pi\epsilon _0r} In Spherical Coordinates do I just use: x=r sin θ cos φ, y = r sin θ sin φ, and z = r cos θ?
  44. A

    Behaviour of hydrogen in an electric field

    behaviour of hydrogen in an electric field... hi, i'm conducting a research in studying the behaviour of hydrogen atom in an electric field and hoping to carryout the stark effect expeiment.i found a hydrogen tube in the lab but the following issues have risen... (1) how do i produce around...
  45. N

    Could Hydrogen and Helium Be the Key to Dark Matter and Dark Energy?

    matter in The universe is thought to be made up of 75 percent hydrogen and helium is thought to make up 25 percent of helium; Dark matter is thought to make up 25 percent of the universe and 75 percent dark energy; that's an interesting coincidence. , and currently physicists are not certain...
  46. C

    Hydrogen Sulfide and Hydrosulfuric Acid

    In our chemistry class, we learned that an acid is a molecular compound that release hydrogen ions when they are dissolved in water through a process called ionization. So are both Hydrogen Sulfide (g) and Hydrosulfuric Acid (aq) acids?
  47. T

    Wave function of hydrogen in 2s state

    Homework Statement Suppose that a hydrogen atom is in the 2s state. Taking r = a0, calculate value for \psi2s(a0) Homework Equations I did spherical harmonics for l=0 ml=0 times the radial wavefunction for n=2 l=0. Got the same thing as the solution manual attached but when I started...
  48. T

    Emission in hydrogen atom - difference between electrons and photons

    A gas composed of hydrogen atoms in the ground state is bombarded with electrons of energy 12.5eV. a) What wavelengths emitted can we expect to observe? b) If we replaced the incident electrons with incident photons of the same energy, what would happen? I know the answers to both...
  49. B

    Compressed Hydrogen tank mass estimation

    Does anyone know how to calculate the mass of compressed hydrogen tank at certain pressure. The tank is cylindrical with hemispherical ends. I have pressure,radius,wall thickness and length,internal volume and density of the material. The tank is a Type IV tank.(Composite tank with...
  50. M

    What would repel, hydrogen / a proton?

    What would repel, hydrogen / a proton?
Back
Top