Questions tagged [hydrogen]

Questions regarding the chemical properties of hydrogen and its behavior in reactions and compounds.

Filter by
Sorted by
Tagged with
3
votes
3answers
3k views

Is water a possible fuel for jet engines? [closed]

Jet engines can run on almost any fuel, and the operating temperatures of modern jet engines' hottest sections are anywhere between 3000 and 3150 degrees F (1648 and 1732 degrees Celsius). Does that ...
2
votes
1answer
2k views

How many peaks of HCl are found in a mass spectrum?

In a mass spectrometer some hydrogen chloride molecules will split into atoms. Chlorine has two isotopes. The hydrogen involved here is the isotope $\ce{^1_1H}$ only. How many peaks does a mass ...
2
votes
0answers
858 views

Allotropes of hydrogen

Is it possible to chemically bond 8 hydrogen atoms together to form an allotrope like $\ce{H8}$?
1
vote
1answer
56 views

Implication of completely non relativistic Hamiltonian

I am studying the Application of perturbation theory to hydrogenic atoms subject to internal or external electromagnetic fields. The very first equation it uses is the hamiltonian of hydrogenic ...
5
votes
1answer
8k views

Reaction between magnesium metal and sodium hydroxide: Does this even happen?

Came across this question in a book: Among aluminum, zinc, tin and magnesium, which metals (if any) will react with an aqueous solution of sodium hydroxide to displace dihydrogen? The answer to ...
6
votes
1answer
309 views

Mechanism for interconversion of spin isomers of hydrogen

What is the mechanism by which the ortho- and para- spin isomers of hydrogen interconvert? If such a mechanism exists, does this mean that ortho-hydrogen increases in concentration on increasing ...
4
votes
1answer
50 views

Hydrogen evolution during thermal spray

Firstly, let me state that I'm no chemist. My specialty is in thermally applied coatings such as electric-arc metalizing. During the course of my career I've always been presented with vague ...
0
votes
1answer
4k views

Can reaction of gastric acid with swallowed things be dangerously exothermic?

Okay, okay. I know that swallowing a large enough amount of any substance would be considered dangerous. That isn't the point of this question, however. As you probably know, the stomach has ...
14
votes
1answer
841 views

Are there any significant uses of the compound formed by magnesium and anthracene?

In an unusual reaction, magnesium reacts with anthracene in THF to form a grignard-like compound called, prosaically, magnesium anthracene: I remember using it briefly in the 1980s. At the time there ...
5
votes
1answer
335 views

Balmer and Paschen Series

If electron makes transition from, in $H$ atom, $6\rightarrow 2$ (to Balmer), then $\bar{\nu}_{{H}_{6\rightarrow 2}}=x$ (let). Also if electron makes transition from, in $He^{+}$ ion, so that $\bar{\...
0
votes
1answer
155 views

Can hydrogen alone be used as a fuel? [duplicate]

I have always thought that fuel such as petrol, diesel, etc.. are getting burnt to move the pistons in the car (I am not bringing physics). Why not hydrogen be used as a fuel but I know the incident ...
0
votes
0answers
274 views

Polarisation of electron clouds by partially positively-charged hydrogen atoms

Premise of my question: I was just wondering about this as I was writing a response to the question (linked here: Bicarbonate decomposition and pKa): Is it possible for partially positively-charged ...
2
votes
3answers
298 views

Where to buy/How to build a Devanathan-Stachurski cell?

I'm preparing to do some hydrogen permeation tests to calculate the diffusivity of some iron samples. I would like to do this using the Devanathan-Stachurski cell, which consists of two cells, one ...
0
votes
1answer
36 views

Why add acid to rid of soluble carbonate or hydroxide impurities? Will it not also react with halide I'm testing for

When identifying metal halides with silver ions, the positive ion $\ce{Ag+}$ will form $\ce{AgX}$ with halide in a solution. However, $\ce{H+}$ is added (typically in the form of an acid like $\ce{...
-6
votes
1answer
550 views

Common hydrogen bonded liquids [closed]

For some experiments I need liquids with and without hydrogen bond which are pure or highly concentrated. I have only found $\ce{HNO3, CH3COOH}$ concentrated. But i need more liquids. And it would be ...
1
vote
0answers
223 views

In a hydrogen fuel cell stack, is pure oxygen required?

I have been researching making a hydrogen fuel cell to produce electricity. However, since pure oxygen is expensive, is pure oxygen needed for the dry fuel cell stack or can the oxygen in the air be ...
0
votes
0answers
36 views

Reaction of acids with water [duplicate]

Here is the reaction of $\ce{HCl}$ with $\ce{H_{2}O}$ I found on a website $$\ce{HCl + H_{2}O -> H^{+}(aq) + Cl^{-}}(aq)$$ However, in my text-book, the reaction is given as $$\ce{HCl + H_{2}O ...
5
votes
0answers
251 views

Compounds that Liberate Hydrogen from Water, Reversibly

I'm working on a paper which provides an overview of all the current methods for storing hydrogen gas as part of a renewable energy system, and I understand compressed gas and metal hydride storage ...
0
votes
0answers
138 views

Relative reacting tendency of H2/Pd towards double bond and triple bond in straight carbon chain

If both double bond and triple bond is present in a straight carbon chain the which one (double bond or triple bond) will be reduced by $1$ equivalent of $\ce{H2(Pd)}$ ? My guess is that the ...
1
vote
1answer
461 views

What types of ultraviolet light will ignite hydrogen?

I saw a reaction between hydrogen and chlorine ignite in the presence of UV light. I was wondering if the same thing would happen with something like near-ultraviolet light (around 400 nm). What kinds ...
0
votes
1answer
123 views

What is the link between hydrogen production and potassium oxide?

Is there an industrial process that produces hydrogen with potassium oxide as a catalyst? Or is there a process for the production of potassium oxide that has hydrogen as a by-product?
2
votes
1answer
987 views

Chemical reactions in plasma state

I am wondering about chemical reactions when the reactants are in a plasma state. Consider hydrogen and oxygen. Heated, these would react to form water. If hydrogen and oxygen plasma were combined, ...
6
votes
1answer
9k views

Why does hydrogen burn with a pop sound?

Our teacher made us to do an experiment with zinc granules and hydrochloric acid. $$\ce{2HCl + Zn -> ZnCl2 + H2}$$ We collected the hydrogen gas that was evolved in a test tube and on ignition, ...
2
votes
1answer
587 views

Can the hydride ion act as a ligand?

Hydride ion, as I know is a pretty powerful base, much stronger than hydroxide ion and cannot exist in an aqueous phase. Can it act as a ligand in coordination compounds? Hydride ion has its ...
1
vote
1answer
359 views

Forming hydrogen sulfide from electrolysis of sodium thiosulfate

So I was doing electrolysis on two silver electrodes and sodium thiosulfate. Some observations The voltage drops extremely fast from 2 V to less than 1 V in 15 minutes, possibly because of the ...
21
votes
5answers
15k views

Is there such a thing as an acid without a hydrogen?

I'm in AP Chemistry and we are learning about the Brønsted-Lowry model and my teacher mentioned that "for the most part" acids have hydrogen, could there be such a thing as an acid that has no ...
2
votes
1answer
153 views

How can I generate 250 GPa to create metallic hydrogen?

In the preparation of metallic hydrogen, how does one conjure up such immense pressures? I mean, I read that something like diamond anvils were used to contain the hydrogen, but now, in accordance ...
2
votes
0answers
130 views

Properties of metallic hydrogen

Given the possibility that metallic hydrogen may have recently been produced, and the massive media bloviation that followed, I am curious about some of the "properties" that I heard from multiple ...
-1
votes
1answer
4k views

Why is the H-H Bond Dissociation Enthalpy so high? [closed]

"The H-H Bond Dissociation Enthalpy is the highest for a single bond between 2 atoms of any element."
12
votes
1answer
3k views

Why are some elements more abundant than others in the universe?

Hydrogen is the most abundant element in the universe. But what makes it so? At the time of big bang, what made certain elements more abundant than the others? I don't find this order of abundance ...
3
votes
1answer
2k views

Why is the entropy of deuterium greater than that of hydrogen gas

Why is the entropy of deuterium more than that of hydrogen gas? I thought about it but couldn't figure out a reason for why that would happen. Why would the number of neutrons in the nucleus ...
1
vote
2answers
2k views

Will Ammonia react with Gasoline mixed with Ethanol?

Recently the South Koreans invented a car that runs on an 70% ammonia 30% gasoline fuel mix. (link) In America we already have instituted policies that require refueling stations to mix Ethanol ...
1
vote
2answers
133 views

Notation of hydrogen

$$\ce{e- + H2O -> [H$\cdot$] + HO-}$$ I was a little confused on the notation of the hydrogen in brackets ([H]) in the product side of the reaction. Why is there a dot next to it and what does it ...
12
votes
0answers
174 views

Densest hydrogen storage medium [closed]

What compounds or nanostructures contain the most hydrogen atoms per unit of volume in realistic conditions (under 1 GPa). Particularly boron-free compounds because it's to be used in sci-fi nuclear ...
2
votes
1answer
1k views

How can difference in neutron number cause a difference in ionisation enthalpies?

It’s a well known fact that protium,deuterium and tritium have the same number of electrons and protons but different number of neutrons. It is expected that their ionisation enthalpies should be same ...
3
votes
1answer
530 views

What is the nature of interstitial hydrides?

In my Chemistry book(NCERT Chemistry,Part 2, textbook for class 11, Pg 281). I found the mention of interstitial hydrides: Unlike saline hydrides these compounds are nonstoichiometric, for ...
8
votes
1answer
1k views

Why do spin isomers of hydrogen (ortho and para hydrogen) change their nuclear spin with temperature variance?

My book says that ordinary dihydrogen contains 75% ortho and 25% para forms of hydrogen, while at significantly lower temperatures (like 20K) ortho and para hydrogens are 0.18% and 99.82% respectively....
11
votes
2answers
4k views

What is the difference between “atomic hydrogen” and “nascent hydrogen”?

My book (Comprehensive Chemistry by Dr. N . K. Verma, S. K. Khanna, Dr. B. Kapila) mentions two forms of hydrogen — "atomic" & "nascent". It says that these two forms of hydrogen are more ...
2
votes
2answers
12k views

Emission Spectrum of Hydrogen and Helium?

Why do hydrogen and helium have different emission spectra? I thought that emission spectra were the result of electrons 'jumping' from one energy level to the next - since hydrogen and helium both ...
1
vote
1answer
96 views

Is Nuclear Spin Isomer a kind of allotrope?

In my book there's a question: Does $\ce{H2}$ shows allotropy ? Enlist its allotropes and their application? I pondered over different way Hydrogen can be arranged(I don't know but I have weak ...
2
votes
1answer
177 views

Hydrogen atom transfer between enantiomers of rac-1-phenylethanol

(Taken from Dalton Trans., 2012, 41, 13423–13428. DOI:10.1039/c2dt31781h) I have difficulties understanding the hydrogen transfer in the image above. I always thought that hydrogen transfers followed ...
4
votes
2answers
6k views

When a molecule loses hydrogen atoms, does it become oxidised?

I had the following question on a bio test covering cell respiration and glycolysis, but I'm not sure if I agree with the answer. When a molecule loses hydrogen atoms (as opposed to hydrogen ions),...
-1
votes
4answers
445 views

Is there any substance that is liquid at room temperature and pressure that doesn't contain H as one it's constituents apart from mercury? [closed]

I want to know if there's any substance that is liquid at room temperature and atmospheric pressure that doesn't contain HYDROGEN atom(s) in its make up. Any substance dissolved in water or any ...
8
votes
2answers
497 views

Oxidation state of hydrogen in the LaNi5H intermetallic

This question is from an introductory chemistry course: What is the oxidation state of $\ce{H}$ in $\ce{NaH}$, $\ce{HCl}$, and $\ce{LaNi5H}$? I've looked in the textbook to no avail. Google ...
1
vote
1answer
580 views

Difficulty understanding redox in terms of hydrogen and oxygen transfer?

I have come across 4 ways of defining oxidation: loss of electrons increase in oxidation number gain of oxygen loss of hydrogen From these definitions, I have an idea of what I think 'oxidation' and ...
1
vote
1answer
238 views

How to calculate the magnitude of magnetic field of an orbital?

I read that according to QM the electron in the ground state orbital produces no magnetic field, if that is true, can you explain why so and in what states there is a magnetic field and how that is ...
3
votes
1answer
103 views

Hydrogenation side product: potential mechanisms for C-C bond making

In the analysis of the product mixture of a new catalytic hydrogenation reaction I'm trying out I am getting this side product molecule (in low quantities; less than 1% w/w). Is this a likely / ...
-4
votes
2answers
2k views

why hydrogen is so light?

I was studying about properties and behaviour of hydrogen and found that hydrogen is lightest element.It is so light that 1 litre of hydrogen at N.T.P weighs only 0.0980 grams. The first statement ...
1
vote
2answers
12k views

Is hydrogen (on its own) considered an acid?

An acid is: A molecule or other species which can donate a proton So when hydrogen appears by itself on one side of a dissociation reaction e.g. $\ce{HOCl -> H+ + OCl-}$ is the hydrogen an ...
1
vote
0answers
53 views

Stability of ortho and para hydrogen [duplicate]

I have two books on inorganic chemistry, one says that ortho hydrogen is more stable while other says para is more stable. Even on Internet, there are websites some supporting the former fact and some ...