What is Methane: Definition and 111 Discussions

Methane (US: ; UK: ) is a chemical compound with the chemical formula CH4 (one atom of carbon and four atoms of hydrogen). It is a group-14 hydride and the simplest alkane, and is the main constituent of natural gas. The relative abundance of methane on Earth makes it an economically attractive fuel, although capturing and storing it poses technical challenges due to its gaseous state under normal conditions for temperature and pressure.
Naturally occurring methane is found both below ground and under the seafloor, and is formed by both geological and biological processes. The largest reservoir of methane is under the seafloor in the form of methane clathrates. When methane reaches the surface and the atmosphere, it is known as atmospheric methane. The Earth's atmospheric methane concentration has increased by about 150% since 1750, and it accounts for 20% of the total radiative forcing from all of the long-lived and globally mixed greenhouse gases. Methane has also been detected on other planets, including Mars, which has implications for astrobiology research.

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  1. Feynstein100

    B Gas diffusion rates for methane into a vacuum versus into nitrogen

    Let's say I have a box with a partition dividing it into two halves. In one half, I have methane, in the other is pure vaccum. When I remove the partition, the methane will diffuse into the other half of the box and occupy the entire volume. This is the first case. In the second case, the setup...
  2. Graeme M

    Is Reducing Livestock Herd Size the Key to Reducing Methane Emissions?

    I am aware that it is claimed that ruminant farming and animal agriculture more generally are significant contributors to anthropogenic emissions. Here in Australia, for example, about 80% of emissions from the ag sector are from methane and nitrous oxide. Various groups propose finding ways to...
  3. agm

    Finding the Equivalence Ratio of Combustion (Methane + Air)

    I'd like to do some experiments with flames at different Equivalence Ratios - but I'm confused as to how I can find the Equivalence Ratio for different conditions. Wiki-article So the stoichiometric balance for Methane + Air is CH4 + 2(O2 + 3.76N2) -> CO2 + 2H2O + 7.52N2 Referencing equations...
  4. moriah

    Microbes & Methane: Are Microbes "Encased" in Gases?

    I apologize. I didn't see any general chemistry categories, so I am posting my question here. Microbes and methane are inextricable from one another. My question is this. Are microbes "encased" in gases like methane when they rise into the atmosphere? Surely microbes can become particulate...
  5. M

    Getting an exact amount of Methane out of a cylinder

    Hello, I am currently working on a research project that involves filling a 10L tedlar bag with about* 8 liters of methane gas from a compressed gas cylinder. I'm trying to work out the best way to fill the bag with a reasonable degree of accuracy while also minimizing (or hopefully avoiding...
  6. moriah

    How Do Methane and Hydrogen Sulfide Contribute to Global Warming?

    Methane and hydrogen sulfide are supposed to be heavier then air, thus why they remain in low lying areas. I am to believe that only when they begin to disintegrate, they rise into the atmosphere. So my question is, if these gases are already disintegrated, how can they be so formidable?
  7. Dukon

    B Trace methane in Uranus and Neptune, condensing into diamonds

    Uranus and Neptune have roughly an 80-19-1 $H_2$-$He_4$-$CH_4$ mixture. (Of course actual percentages vary but those are rough values for sake of this simplification argument -- unless their actual values are critical to the answer.) Uranus temperature is reported as 2K while Neptune is 20K...
  8. Y

    Engineering Find out the percent exergy loss

    Problem, with state values, and pie chart (Fig 4.20) showing answers: ^ This shows the system in question (Kapitza Liquefaction System). Methane gas enters into the compressor (c), then goes through the first heat exchanger (HX1). Some of it (z) gets routed to the expander (exp). Afterwards...
  9. Graeme M

    Radiative Forcing of Methane in Shortwave

    I was doing some reading about the extent to which methane absorbs in bands already dominated by water vapour and came across this paper. Two things stand out for me - first is that according to the authors the RF of methane is increased by 23% due to previously underconsidered shortwave...
  10. gleem

    B Where has all the methane gone?

    Recent assays of atmospheric methane by the Trace Gas Orbiter did not find any quantifiable amounts of methane in Mars atmosphere. Previously amounts in pp billion have been documented by surface survey vehicles but the TGO put an upper limit in the atmosphere of 12 pp trillion. It is known...
  11. BillTre

    Methane and Organic Molecules on Mars

    Curiosity has found seasonal occurrences of methane and some organic molecules on Mars. Both or possible indicators of carbon based life processes, but can have other non-biological explanations. Methane has been intermittently found previously on Mars. However, lacking a continuous long term...
  12. A

    Can we sequester methane by pumping air through soil?

    Methanotrophs already exist in most soils. If we expose them to more methane, will they eat more? A solar powered fan blowing air down a tube that ran along under soil, with lots of small holes along its length - would that reduce the methane in the air? As a second part to the question, does...
  13. M

    I Dissolved gas concentration in undersaturated liquid column

    Hi, In an enclosed system - of say Methane & water - in which the water column is sufficiently large to have significant pressure and some modest temperature difference due to gravity and geothermal effects, how would one calculate / predict the changing methane concentration (or partial...
  14. G

    Acidity of TMS Acetylene vs Methane

    Homework Statement Between trimethlysilylacetylene and methane, which is more acidic and why? Homework Equations No equations The Attempt at a Solution I believe the answer is trimethylsilylacetylene due to the location of the alpha proton being at the end of the alkynl group and with...
  15. Aafia

    Does the amount of energy affect the dissociation of methane

    I hear that methane is known dissociate into free radicals and sometimes into ions (carbocation and hydrogen proton). Is it different amounts energy responsible for the same molecule (methane) to undergoing different kinds of dissociation?
  16. I

    Methane mixed with air at 16:1 by mass

    Homework Statement Methane is mixed with air at a 16:1 per mass ratio at 1atm and 298K. Calculate the mass fraction of argon, nitrogen, oxygen, and methane in the final mixture Homework EquationsThe Attempt at a Solution First, change mass ratio of reactants to mole ratio $$ \frac{16 g...
  17. wolram

    Are the 500 Newly Discovered Methane Vents a Cause for Climate Change Concern?

    I do not know if this is a worry but it seems like our oceans are leaking green house gases. https://www.sciencedaily.com/releases/2016/10/161020103858.htm Date: October 20, 2016 Source: National Ocean Exploration Forum Summary: Five hundred vents newly discovered off the US West Coast, each...
  18. N

    Methane production and storage

    Hello members, I wish to produce and "store" "Methane" gas. I wish to accomplish this task by conducting out a reaction between carbon-dioxide an water. I have my own source of energy and I completely understand that the reaction is endothermic. The reaction is: CO2 + 2H2O + energy = CH4 + 2O2...
  19. J

    Substitution reaction between methane and bromine

    We can react one mole of ##CH_4## and one mole of ##Br_2## to obtain the following equation: ## CH_4 + Br_2 \rightarrow CH_3 Br + HBr ## A single bromine atom switches places with a single hydrogen atom. Now, if we supply a greater amount of ##Br_2## while keeping the amount of ##CH_4## the...
  20. Aestheticia

    Methane as a substitute for petroleum in combustion engines

    Dear engineering community: For many years now I have wondered why our internal combustion engines have not been adapted for methane in place of the various forms of petroleum products we currently use. Why? (1) Because we have a gargantuan ever-renewing source of methane in human garbage...
  21. T

    Standing wave in a column of methane, find gamma of methane

    Homework Statement A standing wave with a frequency of 1100 Hz in a column of methane at produces nodes that are 0.200 m apart. What is the value of γ for methane? (The molar mass of methane is 16.0 g/mol)Homework Equations v = sqrt ( γRT/M) where R is 8.341, T = 20 °C and M = 16.0 g/mol. v=fλ...
  22. M

    A How to calculate energy levels of methane. (given v and J)

    I have previously learned about the energy level calculation of some diatomic molecules, such as N2 and CO. Now I need to calculate the spherical top symmetric molecules like CH4. But I cannot find the force constants for it either, can anyone give me some suggestions about this?
  23. D

    Can Methane and Citric Acid be Balanced in a Redox Reaction?

    Hi there: I'm trying to balance a reaction in which methane is oxidized by citric acid in solution. Both methane and citric acid will be transformed into carbon dioxide. To begin, I checked that the reaction is indeed a redox reaction. C6H8O7→CO2 So, I calculated the oxidation number for...
  24. Hyo X

    Ammoniation of Cattlefeed on Bovine Methane emissions

    Has this study been done? It seems the ammoniation [using ammonium hydroxide] of low-quality straw to increase digestibility of the feedstock is an established practice. Also, cows are a pretty big producer of methane, a significant greenhouse gas. Does treating with ammonium hydroxide the...
  25. C

    Geometry of Methane: Finding the Distance Between Hydrogen and Carbon Atoms

    Homework Statement In a methane molecule, determine the length of the distance between a hydrogen atom at A and the carbon atom at O (see diagram) in terms of the length of the edge (e) of the cube at four of whose corners the hydrogen atoms rest. Homework Equations pythagorean theorem...
  26. Stephanus

    Producing Methane from Sugar - PF Forum

    Dear PF Forum, Can anyone help me? I'd like to know what is the reaction that produces methane from sugar? I believe it's reduction. This is sugar oxydation: C6H12O6 + 6O2 -> 6CO2 + 6H2O What is the reaction to produce methane from glucose? C6H12O6 + ? -> CH4 + ? And please if you would be so...
  27. Stephanus

    Producing Methane from Composting: Benefits & Process

    Dear PF Forum, I'm interested in composting. I want to understand the benefit of composting. Besides Reducing organic waste Producing fertilizer This composting process also produce energy (methane) if properly managed. I wonder how, without oxygen addition/introduction, in a sealed composter...
  28. Stephanus

    How much methane is produced from 1 kg of typical organic waste?

    Dear PF Forum, Next month there will be an environment activist gathering in my church. I want to introduce to them one of the benefits of organic waste. It's methane production. Organic waste will produce methane, and in turn it is the source of energy. What I want to know is how much methane...
  29. Stephanus

    Percentage of hydrocarbons in living organism

    Dear PF Forum, I'm interested in how much energy our organic waste contain. I have read this article https://en.wikipedia.org/wiki/Composition_of_the_human_body Elements composition of plants The elements composition of human body (and animal?) and plants resemble. Bacteria has slightly...
  30. Stephanus

    How can I calculate heat of combustion and enthalpy using Hess's Law?

    Dear PF Forum, I have read this link in Wiki. But I don't understand what it means. Can someone help me? https://en.wikipedia.org/wiki/Heat_of_combustion A: Heat of combustion of CH4 is 50.09 MJ/kg https://en.wikipedia.org/wiki/Standard_enthalpy_change_of_formation_(data_table) B: Enthalpy of...
  31. J

    Average C-H bond energy in methane

    Homework Statement "By means of a balanced chemical equation, including state symbols, illustrate the term average C-H bond energy in methane." Ans: CH4 (g) -> C(g) + 4H(g) Average bond energy = +x/4 kj/mol Why C (g) ? Why is the state of C gas?
  32. UMath1

    Landfill methane gas emissions

    I read that biodegradable waste in landfills produces methane, a harmful GHG. But didn't biodegradable waste always exist? We throw paper away, but the trees we produce paper from would have died eventually. Our organic waste comes from plants and animals that would have died eventually too. So...
  33. S

    Gases compression at critical point. LNG (Methane) storage.

    There are claims or at least assumptions that: "upon approaching "critical point" pure gases become super compressible. You could compress them many times without pressure increase and store like this if you maintain exact temperature and pressure needed. It opens possibility to superdense gas...
  34. B

    The Potential of Titan: Igniting Methane Oceans for Photosynthesis

    If a methane-filled planet or moon like Titan was pulled toward a star, as the methane warmed and became gaseous, would it be possible to ignite it, converting the methane oceans to H2O with a CO2 atmosphere, which could in turn cause photosynthesis to naturally occur? If it's possible, it...
  35. A

    How to Calculate Energy for Atmospheric Molecule Reaction and Isolate Gases?

    The atmosphere consists of two toxic, and unfortunately abundant gases in our atmosphere. Carbon dioxide and methane. Carbon dioxide produced by factories are not needed in the atmosphere and cause harm. So is methane. Acegikmoqsuwy and I thought of an equation to solve this problem: CH4 + CO2...
  36. P

    Why does Methane lack 90 degree angles?

    With the Methane structure of CH4 and an electron structure of Carbon as 1s22s22px12py1 and the electron structure of Hydrogen as 1s1 with P-orbitals separated by 90 degrees from each other and S-orbitals uniform spheres why aren't two of the Hydrogen atoms in a Methane molecule at 90 degree...
  37. M

    How fast would a methane cloud rise in air?

    Homework Statement Hi everyone, This is a conceptual question, so there are no variables, per se. I'm trying to figure out how to calculate the velocity at which methane would rise into the atmosphere when released on the ground. Density of air: 1.225kg/m^3 Density of methane: 0.717kg/m^3...
  38. O

    Produce Methane Via CO2 + H2O ?

    it is known that the standard combustion enthalpy of methane is -882 kJ/mol CH4 + 2 O2 --> CO2 + 2 H2O Hc = -882 kJ based on hess's law, if a reaction is reversed, so does with the enthalpy CO2 + 2 H2O --> CH4 + 2 O2 Hc = +882 kJ which makes the reversed reaction become...
  39. I

    Making Methane a More Useful Fuel: Catalyst Possibilities?

    This might be a stupid question so forgive me if it is. I am looking for a way to make methane more useful as a fule and it seems to me that to do that I would have to make it into a longer hydro-carbon chane. Is there a catalyst that could be used to do this? Thanks in advance.
  40. caters

    Free Radical reaction of methane and Chlorine

    Homework Statement Lets say you have 1 liter of 2 mol/L methane and the same amount of chlorine. Let's also say that both are liquids since those are most likely to react. Now the only way they can both be liquids is if the temperature is as cold as an antarctic winter so this is not aqueous...
  41. E

    How Is Entropy Calculated During Isothermal Expansion in a Carnot Engine?

    Homework Statement A Carnot engine operates with 1 kg of methane, which we will consider an ideal gas. The ratio of specific heat capacities \gamma is 1.35. The ratio of maximum volume to minimum volume is 4 and the cycle efficiency is 25%. Find the entropy increase during the...
  42. I

    How to Purify Methane from Biomass for Clean Burning?

    Hello does anyone know an easy way to purify methane made from biomass? I am not sure what gases I am producing but i know i have methane, CO2 and water vapor, and maybe hydrogen sulfured judging from the smell. I want to get a product clean enough to burn in place of nature gas. Thanks for the help
  43. I

    Compress Methane Safely Without Risk of Explosion - Sam

    How can i compress methane without a risk of it exploding? I want to compress methane generated form biomass into a storage tank (a small propane tank) without flattening my workshop. Does anyone know a safe way to do this? Thank Sam
  44. K

    Chemistry: Methane - Oxygen Combustion Problem - Help needed please.

    Hello, Please help me with the following problem. Homework Statement 0.10 Liter of Methane (CH4) gas, at a temperature of 25C and pressure of 744mmHg, react with Oxygen (O2) gas, at constant pressure. The heat released during the process is then transferred to an "ice...
  45. C

    Methane and CO2 atmospheric lifetime math problem

    Homework Statement On a per-molecule basis, methane is 26 times more effective as an infrared absorber than is CO2. Calculate the corresponding ratio on a per-unit-mass basis, and compare it with the 20-year GWP for methane. What's the reason for any discrepncy you find? (CO2 atmospheric...
  46. Z

    Using Henry's law for dissolved methane in a well

    Suppose water at the bottom of a well contains dissolved methane. When the water is pumped up, the dissolved gas is released. How many moles of methane gas will be released if the well is 115 m deep and holds 2 L. Assume a Henry's law constant of 2.97 x 104 atm at 10o C (at the bottom of the...
  47. T

    On carbon, methane and electromagnetic radiation

    iTunes University layman looking for answers and willing to do the work – just need some direction. I now understand electromagnetic waves can be created when molecules vibrate – which they all do. I understand the frequency of the light correlates to the frequency of the molecular vibration –...
  48. C

    Methane? how much will it expand if we vapourize it

    If we have 1m3 of methane liquid at 1 atm and -165 degrees, how much will it expand if we vapourize it? I have heard someone say that it expand with 600 times.
  49. C

    Explaining H-N-H Bond Angle in Ammonia vs H-C-H in Methane

    Homework Statement Explain why the H-N-H bond angle in ammonia is less than that of H-C-H in methane. Though this is a worked example. I just want to understand the explanation given for the problem. Homework Equations The Attempt at a Solution As I said, this is a worked...
  50. C

    Why methane burn at high temperature?

    Methane burns at 1200k without any spark or ignition. But why is this so?Why so high temperature? Isn't it that when there is the right proportion of methane and oxygen, combustion will occur with a small energy needed? Or is it because of high activation energy?