Questions tagged [hydrogen]
Questions regarding the chemical properties of hydrogen and its behavior in reactions and compounds.
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Why only Balmer series of hydrogen spectrum is visible?
When I was reading about the hydrogen spectrum, I came across the statement:
Only Balmer series of hydrogen spectrum can be visible to our eyes.
I really got surprised by that. Why can't other ...
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Mechanism of Zn + NaOH?
I was reading block chemistry in class, and I was taught by my chemistry professor this method of preparation of hydrogen:
$\ce{Zn + NaOH -> Na2ZnO2 + H2}$
In this reaction, zinc reacts with ...
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Sensitivity of CoSi2 to hydrogen
It is known that palladium is quite sensitive to hydrogen, i.e., has an extraordinary ability to absorb hydrogen. I was reading a paper that talks about the fabrication of a Pd based sensor for ...
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Why is my Ni or Fe cathode blackening and pores getting blocked during alkaline (6 M KOH) electrolysis?
I am conducting an electrolysis process for hydrogen $(\ce{H2})$ and oxygen $(\ce{O2})$ generation using a $\pu{6 M}$ $\ce{KOH}$ alkaline solution.
During the process, I have observed that my cathode ...
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Why is the translational motion left out of the energy eigenvalue in the hydrogen atom?
When solving the hydrogen atom, since we have two particles, the wave function has the form $\psi(\mathbf{q}_1,\mathbf{q}_2)$. Generally, textbooks proceed to demonstrate that an interacting two-...
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Waste Products from Hydrogen Fuel Cells
I was recently reading this article by BMW, that said
The exhaust air of a hydrogen car consists of pure water vapor. The fuel cell drive is therefore locally emission-free. This means it keeps the ...
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How many neutrons could a hydrogen atom hold?
Usually a hydrogen atom consists of no neutrons; however many exotic hydrogen isotopes have been synthesized. Deuterium and tritium are some of the more 'common' isotopes; nevertheless, Wikipedia's ...
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Resolve inconsistency regarding percentage of ionized water molecules in the auto-ionization of water
I am relearning some chemistry in order to understand pH for a particular application. My last encounter with the subject was in high school several decades ago. I have the following question:
I read (...
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Devanathan / Stachurski cell, hydrogen permeation in palladium
The cell mentioned in the title is a couple of electrochemical cells separated by a metal diaphragm. On the surface of the diaphragm, on one side, hydrogen is evolved. The amount that permeates is ...
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Calculation of Kc
Gaseous hydrogen and gaseous iodine react together to form hydrogen iodide.
H2 + I2 ⇌ 2HI
The graph shows how the amount of hydrogen iodide varies with time in a 1.00 dm3
container.
The initial ...
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Deriving Nernst Equation for a hydrogen-oxygen Fuel cell
Reading across electrochemistry books (particularly the fuel cells chapter of the book "Alternative energy systems and applications" by Hodge) I came across the following formulae:
$$\Delta ...
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Simple Calculation of Potentials for a hydrogen-oxygen Fuel cell, unexpected results from book example
I am reading "Alternative energy systems" by Hodge.
On the fuel cell section, the author has an example for calculating the potential required for the fuel cell as a function of temperature ...
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Do solvated electrons short circuit the electrolysis of liquid ammonia
If attempting the electrolysis of liquid ammonia using NaNH2 as an electrolyte. It is understood that Na+ will form solvated electrons. I understand that these solvated electrons can dramatically ...
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Hydrogen Peroxide 60% Dilution [closed]
Can anyone please help me? I have used various 'dilution' calculators' online, and done the equations on paper. However I DO NOT want to get this wrong and one can be great at math, but help and ...
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Solubility of hydrogen
I'm interested in bacterial fermentation which produces molecular hydrogen as an end product. If bacteria produce molecular hydrogen in solution under anaerobic conditions, does this remain dissolved ...
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Why doesn't sodium bicarbonate dissolved in water spontaneously effervesce when carbonic acid does?
It's well known that if you put carbonic acid $\ce{H2CO3}$ into water it will dehydrate into carbon dioxide $\ce{CO2}$ and water $\ce{H2O}$. Indeed this is how modern fizzy drinks generate their fizz. ...
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Self heating of Hydrogen
I have read that hydrogen can undergo self-heating, through a catalytic process, without the presence of oxygen or air. Is that true?
I understand that this is not "burning" or "...
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Reduction of benzylic alcohol and halide using H2 and Pd
I am studying drug synthesis, and I found some examples that uses $\ce{H_2}$ and Pd/C or Pd/$\ce{BaSO_4}$ as catalytic hydrogenation reagents for reduction of alcohol or halide in benzylic position. ...
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H-NMR Analysis of C15H24O
I was able to figure out that the structure of this compound was a benzene ring with 2 equivalent trimethyl groups to give the 18H singlet. Another non-equivalent methyl group to give the 3H singlet. ...
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Is size or electronegativity more important in acidity?
For the molecule below, is the hydrogen with the oxygen more acidic or is it the one with sulfur?
Since both parts have the same number of resonance structures, I'm guessing it just boils down to ...
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Is it possible to make a reversible "Solid State" Hydrogen fuel cell using Ammonia Borane and Iron Oxide? [closed]
Well, I saw this video about hydrogen reduction, in which pure hydrogen gas is exposed to iron oxide at high temperatures, producing water vapor and leaving pure iron behind.
And as such, I wondered ...
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Why is tritium radioactive?
The nucleus of tritium (hydrogen-3, $\ce{^3H})$ contains one proton and two neutrons. Nothing repulsive is acting on the proton that can make the nucleus unstable. Then why does it decay?
I suspect ...
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What are disadvantages of methane or ammonia compared to dihydrogen for metal ore reduction?
Metallurgy, such as steel-making processes, require reducing agents to get rid of the oxygen in metal ores. Using fossil coal for this is a large source of $\ce{CO2}$ globally. Recently, I have read a ...
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Relationship of acids and bases with pH. (Proportional Relationship) [duplicate]
Can someone please clarify the relationship between acidic-basic strength and pH? I have come across conflicting information and am unsure about the correct understanding.
Some people including my ...
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How do the orbitals in atoms synchronize their phases during the formation of a bond?
Suppose I have two hydrogen atoms, each with one electron in their 1s orbital. Then we can represent the wave functions of these two as say $|\Psi\rangle_1$ and $|\Psi\rangle_2$ for each of the two ...
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Does Hydrogen Gas need to be bubbled in during Reduction of the electrode?
I have read in textbooks and websites that hydrogen gas needs to be bubbled into the SHE (Standard Hydrogen Electrode). I understand why for oxidation of the half cell - the gas is oxidised into H+ (...
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Chemical Test for Hydrogen
I know that to perform a chemical test for $\ce{H2}$ we have to take a burning candle flame near to the mouth of the test tube and a blue flame with a characteristic pop sound confirms the presence of ...
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Is potassium Sulfate a good electrolyte for the production of oxy-hydrogen?
I am currently conducting an electrolysis experiment using a 30 amp power supply with a voltage ranging from 10 to 16 volts.I am thinking of using potassium sulfate (K2SO4) dissolved in water as an ...
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Ortho- Para- Hydrogen Names and Benzene
I read that the Hydrogen atoms with nuclear spin in same direction are called Ortho- Hydrogen whereas those in opposite nuclear spin are Para- Hydrogen. But is there any resemblance of such a ...
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How do metal hydrides behave in a non-hydrogen closed system?
I am curious about the fundamentals of metal hydrides and how adsorption/desorption works in non-hydrogen systems. My understanding is that the atom ratio M/Hx of the metal hydride is a function of ...
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Why do H and Li bond so differently with a hydroxide?
I am sure I am asking a very basic question but before coming here, I have made multiple attempts to find an answer elsewhere. Or maybe I am simply asking the wrong question, in some sense. If someone ...
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Can molecular hydrogen form hydrogen bonds?
Basically, I want to know if molecular hydrogen (H$_2$) can form hydrogen bonds with other molecules (CH$_4$, CO$_2$, N$_2$). I'm trying to model the mixture of these molecules with SAFT equations of ...
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Mystery GC peak appearing between 1H2 and various molecular combinations of 1H, 2H and 3H?
The following gas chromatograph, taken from "Review of the different techniques to analyse tritium", labels all but the largest peak. Given that the analyte is likely to be from some source ...
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Using Hydrogen as a carrier gas for a GC; consideration of reactivity with analytes
In many cases people use H2 as a carrier gas for a GC. But does this exclude analysis of (say) systems with unsaturation or aromatic compounds etc. If a analysis uses a temperature program say up to ...
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Determining volume of hydrogen gas evolved in water splitting reaction
I want to carry out a photocatalytic water spliting reaction. This reaction will generate Hydrogen and Oxygen gas in 2:1 ratio according to the following reaction -
2H2O + energy (light) → 2H2 + O2
So,...
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How does hydrogen and oxygen combine to make water? [closed]
When two hydrogen atoms fuse with one oxygen atom to create a molecule of water, each hydrogen atom donates its single electron to the oxygen atom, resulting in 10 electrons for the oxygen, instead of ...
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Do PEM Fuel Cells suffer CO poisoning at the oxidizer side?
Reading about PEM Fuel Cells, first on Wikipedia then on some other sites, I notice they talk a lot about the problem of CO poisoning. But almost always it's explicitly referred to as a problem in ...
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Difference between sodium aluminate and sodium metaaluminate
So I was studying Chemistry (Hydrogen - Uses, Properties and Preparation) from 2 different textbooks (based on Grade 9 syllabus, I.C.S.E. Board, India) and I found what seems an astounding anomaly to ...
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Are hydrocarbons compounds of hydrogen and carbon, or carbon and hydrogen?
Is it the same to say "Hydrocarbons are compounds of hydrogen and carbon." as saying "Hydrocarbons are compounds of carbon and hydrogen."
I got a B in my chemistry test just ...
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When hydrogen and oxygen reacts, what defines if it will turn into hydrogen peroxide or water?
If you have a jar with oxygen and hydrogen inside, I'm interested in knowing what variables are most important to ensure that the mixture will become water (if that was the goal) or hydrogen peroxide, ...
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Average molecular distance between hydrogen gas [closed]
The whole question goes like this:
Calculate the de Broglie wavelength of hydrogen molecule at 300K (Take the translational energy to be 1.5kT) Compare this to the average intermolecular spacing for ...
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Can deuterium be separated from heavy water via electrolysis? It is an isotope of hydrogen, so I guess it should act in the same way?
I was wondering if it is possible to separate deuterium from heavy water via electrolysis.
Also, is this the way deuterium gas is obtained on an industrial scale, or are there better methods?
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How to calculate the solubility for the hydrogen concentration based on the pressure and temperature in the Metal Hydride Hydrogen compressors?
My name is Ketan Karkare and I am a student in the University. I am currently working on the metal hydride compression and have gone through the following paper: Mathematical modeling for the PCT ...
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Titanium-free catalysts to decrease decomposition temperature of magnesium hydride
Magnesium hydride $(\ce{MgH2})$ is a metal hydride with a relatively stable structure, at least compared to other metal hydrides. Magnesium hydride splits at around 300 °C into magnesium and hydrogen. ...
user123716
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Has dilead hexahydride been synthesised?
Dilead hexahydride is listed on Wikipedia as a compound composed of two lead atoms, and six hydrogen atoms:
H H
| |
H-Pb-Pb-H
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H H
As the wikipedia ...
user123716
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Confusion regarding classification of hydrides
According to my book,hydrides are classified as Ionic/Saltlike/Saline Hydrides, Covalent/Molecular Hydrides and Metallic/Non-stochiometric/Interstitial Hydrides.
The explanation of my book is not very ...
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Conditions for Pd/C reduction of alkene
I am trying to do a $\ce{H2}$ reduction of cyclic alkene (otherwise simple hydrocarbon with 1 methyl group along with the chain about the weakly-strained cycle) using $\ce{Pd/C}$, the cycloalkene ...
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What material(s) can offer similar performance to polyurethane in a paint coating, but with less hydrogen?
We need to coat parts of an neutron instrument with a boron shielding coating. This currently is achieved using an airbrush gun with a paint mix of demineralized water, polyurethane and boron powder.
...
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What will be the product of 1 eqv Benzene reacts with 1eqv H2? [closed]
how equivalent concept is applied in the above problem, Kindly help me out with the answer and proper explanation.
As, I am getting confused in mole concept and equivalent concept here.
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What are oxidation numbers of each element in CuH?
My chemistry teacher said hydrogen when bonded with metals has oxidation number (O.N.) of −1 except CuH: in CuH the hydrogen has O.N. +1 and the copper has O.N. −1.
But on the internet it is ...