It is an exothermic process by which a substance is oxidized (by an oxidizing agent such as oxygen) to release a large amount of energy in the form of heat and/or light.

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What are the differences between diesel and unleaded gasoline?

I am curious about the flammability of diesel fuel and its properties, as I don't deal with it on a regular basis (at all). In particular, I want to know how the fuel works when powering a diesel ...
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1answer
78 views

What is a kg.cal per gram, as a heat of combustion?

I see heats of combustion given in kg [dot] calories per gram molecular weight (Handbook of Chemistry and Physics, 1969-1970). I don't know how that makes sense, as I don't know what a kg cal might ...
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1answer
34 views

test tube cracked when added glycerin to potassium permanganate

I am not expert in chemistry.I learned about combustion in reaction when added glycerine to potassium permagnet.I tried it at home, I took potassium permagnet in test tube and when I added glycerine ...
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44 views

Methylation of perchlorate

I am exploring (non-experimentally!) the methylation of a perchlorate precursor, either the acid or pre-existing salts, to produce the alkali methyl perchlorate. The methylating agent would be methane ...
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1answer
64 views

Predicting incomplete combustion?

I understand the concept of incomplete combustion and that it occurs when oxygen is not a large enough supply to allow for complete combustion. My question is: how can we model combustion properly in ...
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39 views

Combustion of halo-organic compound

My question is based on the Preparatory Problem Set for the 47th IChO Problem 26 - Holy War against Four Horsemen of the Apocalypse (it is on page 36). It is written that cooling of Y combustion ...
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1answer
58 views

Can you melt wood?

We talked about it in our chemistry class but we couldn't get to a conclusion, any help?
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1answer
66 views

Burning a diamond produces how much energy?

How much energy is produced by burning a 1 ct. diamond? I'm trying to figure out how much energy to build the diamonds in a biological process. See here: ...
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1answer
176 views

Air contain 20 % O2 by volume. How many cm³ of air will be required for oxidation of 100 cm³ of acetylene?

Air contain 20 % $\ce{O2}$ by volume. How many cm³ of air will be required for oxidation of 100 cm³ of acetylene? (a) 1064 cm³ (b) 212.8 cm³ (c) 500 cm³ (d) 1250 cm³ Answer: (d) My ...
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37 views

How do I balance the reaction equation for combusting 1mol of 70%Butane 30%Propane gas mix, with excess air?

I am trying to work out how much water will be produced from the combustion of 1 mole butane/propane gas mix with air for an engineering project.
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1answer
37 views

Is it possible to find fire outside the Earth?

Excuse me if the question is silly, I have very little knowledge of chemistry. We can find oxygen in many places in the universe, but all the combustibles we use to light fire seems to be organic: ...
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1answer
29 views

Can covalently bonded hydrocarbons be influenced by a magnetic field?

I am doing a University project on Magnetically Assisted Combustion and am curious to know more about how magnetic fields may or may not affect gases such as butane and propane. I think I am right ...
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1answer
73 views

Chemical equilibrium for simultaneous dissociation reactions

While calculating the adiabatic flame temperature for the following combustion reaction: $$\ce{\Phi\, C2H6 + $3.5$\,(O2 + $3.76$\,N2) -> $a$\,CO2 + $b$\,CO + $d$\,H2O + $e$\,H2 + $f$\,O2 + ...
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1answer
127 views

What is the enthalpy of combustion for ethene given the values of enthalpy of formation?

I have answered this question and got a value of $\mathrm {1409 \space kJ\ mol^{-1}}$ however, the answer sheet says $\mathrm{-1009}$. Using the equation: $$\ce{C2H4 + 3O2 -> 2CO2 + 2H2O}$$ I ...
2
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1answer
27 views

“Alkanes must be vaporised before they will burn” - what does this mean?

What does this sentence mean - I assumed that burning vaporised something? If something is vaporised, isn't that turning it into a gas? How can you burn a gas? This is a sentence in my AS Chemistry ...
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1answer
64 views

Can paper burn without oxygen or air?

i.e: If you put a paper inside an oven vacuum packed and go beyond 250ºC, will it burn? There's no oxidizer. If not, what will happen?
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13 views

What would be the products? [duplicate]

So today in chemistry I did a lab by reacting calcium carbide with water to form acetylene gas. I brought a burning splint to the mouth of every test tube and waited until a reaction was complete. One ...
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43 views

Combustion in liquid state

Normally, we think of combustion as occurring only in the gas phase. I think I understand the main reason for this - in the gas phase it's very hard for a bimolecular reaction to produce a single ...
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1answer
45 views

Question regarding molar heat of combustion

Hi, I am able to do this question without the "80% of the heat released was absorbed by the water" part, and ended up getting 892.2g How, does "80% of the heat released was absorbed by the water" ...
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1answer
325 views

Equivalence ratio explained

To let you know where I'm coming from: I haven't studied chemistry since high school. I am now studying something else, but I have a dataset coming from your field and I would like some help in ...
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0answers
25 views

How do things heat one another? [duplicate]

For example, how does a gas stove heat a metal pot? A combustion reaction between the gas and the air takes place, and this releases energy due to new chemical bonds being formed. Do the atoms in ...
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2answers
52 views

Is it possible to combust a plasma?

In what we usually consider combustion your fuel and oxidizer are always neutral, but is it possible to have a similar "explosive" combustion process where both the fuel and oxidizer have been singly ...
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1answer
67 views

Creation and Combustion of Nitrocellulose

I am intending to demonstrate the formation and combustion of nitrocellulose with my high school students, however I am concerned about the potential products of the combustion equation. I have been ...
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1answer
34 views

Calculating moles of Hydrogen gas in multiple gas container

If there was a 500 mL container filled with oxygen and hydrogen so it burns completely (2H:1O), how many moles of hydrogen gas would there be if there if pressure is 101.3 kPa and the temperature is ...
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1answer
72 views

Why do internal combustion engines only burn to carbon monoxide, not dioxide?

Why don't diesel and regular car engines burn all the way to $\ce{CO2}$?
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1answer
80 views

Can we do combustion caused by limited supply of air in a lab? How?

For example Ethyne in combustion by limited supply of air $$ \ce{ 2C2H2 + 3O2 ->[\Delta] 2CO2 + 2H2O + 2C } $$ vs. $$ \ce{ 2C2H2 + 5O2 -> 4CO2 + 2H2O + Energy } $$ What are the ...
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1answer
87 views

Can there be active THC be trapped in the evaporator?

In relation to the vaporization of THC, when smoked, is it possible that there is any active THC residue that becomes trapped inside the evaporator after the flame goes out? Wouldn't some of the ...
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2answers
133 views

How to determine the empirical formula for terephthalic acid from its combustion products?

Terephthalic acid is an important chemical used in the manufacture of polyesters and plasticisers. It contains only $\ce{C}$, $\ce{H}$, and $\ce{O}$. In one experiment, $0.4953~\mathrm{g}$ of the ...
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1answer
164 views

How much oxygen is necessary for the combustion of ethane? [closed]

Dicarbon hexahydride plus oxygen creates $\ce{CO2}$ and $\ce{H2O}$. How many oxygen atoms are needed to make $128.4~\mathrm{g}$ of $\ce{CO2}$?
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1answer
53 views

Which enthalpy changes map to the alternative reaction routes under Hess' law?

I am searching for a method that would always allow me to determine which enthalpy changes map to which reaction routes using Hess' law. For example this exam question: And then I end up doing ...
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1answer
51 views

Why does a smaller amount of propanol burn slower than a much larger amount?

Why does $30~\mathrm{mL}$ of $\ce{C3H7OH}$ burn in 1 second (inside a water jug) compared to a sixth of the amount: $5~\mathrm{mL}$ of $\ce{C3H7OH}$ (on a plate) burn in 180 seconds? Why does the ...
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0answers
51 views

Auto ignition of tert-butyl mercaptan mixed with mineral oil

I am designing an experiment that involves immersing pieces of pipe lining in a mixture of tert butyl mercaptan (2%) and white mineral oil (98%) at 23 oC (the standard temperature for the test). If I ...
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1answer
26 views

How significant is air decomposition on NOₓ formation?

How significant is $\ce{NO$_x$}$ formation from $\ce{O2}$ (reactant) and $\ce{N2}$ decomposition from simply heating the two as opposed to from $\ce{CO2}$, $\ce{H2O}$, (and $\ce{N2}$) dissociation? In ...
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1answer
89 views

Write the combustion equation of C5H10O

Like the title, have no idea at all, can someone help me? Should I add $\ce{O2}$ to make it $$\ce{C5H10O + O2 → ..... ?}$$ Full process will be really appreciated ! Thanks for your help!
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3answers
72 views

Fire resistance of PVC

In a paper that I'm reading, it states that The presence of Chlorine atoms in polyvinyl chloride make it flame resistant and I'm just wondering why the presence of Cl will make it flame ...
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1answer
63 views

Why is CO a major species only in fuel-rich combustion?

In fuel-rich combustion, my understanding is that enough fuel reacts and consumes all of the oxygen present. The combustion products $\ce{CO2}$ and $\ce{H2O}$ undergo dissociation until equilibrium is ...
5
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1answer
120 views

Is There a Difference in the Definition of Complete and Stoichiometric Combustion?

My question has to do with some combustion related definitions. When the term complete combustion is used, is it assumed that the combustion is stoichiometric (reactants combine perfectly), but ...
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1answer
278 views

Combustion of paraffin

Find the heat of combustion for 1 mol of $\ce {C21H44}$ in the reaction where some wax is oxidized to elemental C (soot) and water vapor. The Heat of Formation of $\ce {C21H44}$ is -476 kJ/mol. When ...
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204 views

Relationship between Auto-Ignition Temperature with Pressure and Fuel

Experimentally it appears that increase in pressure, fuel concentration, and chain length causes AIT to decrease until a minimum where even further increase in these parameters increases the AIT. ...
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1answer
51 views

Greatest Energy Output Reaction to Atmosphere Air

First of all i'm no chemist, this is not homework and if you need further clarification please ask. I'll be happy to provide! Imagine that you: have 1 kg of any given chemical X A car battery A ...
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1answer
60 views

Additional Questions Regarding the Auto-Ignition Temperature

I had some followup questions regarding a previous post I made here regarding the auto-ignition temperature and ASTM E659 For fuel temperature below AIT, we should still have finite reactants above ...
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1answer
191 views

Mechanics Behind the Auto Ignition Temperature

I have some questions about the auto-ignition temperature for fuels. Per ASTM E659: AIT (auto-ignition temperature) is the lowest temperature at which the substance will produce hot-flame ignition ...
2
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0answers
376 views

Relationship between Equivalence Ratio and Adiabatic Flame Temperature for Fuel Rich Combustion

I'm reading a combustion text and would like help interpreting the following passage (diagram attached). It is regarding the relationship between equivalence ratio and adiabatic flame temperature: ...
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1answer
127 views

Do reverse reactions occur in combustion?

I am currently reading a textbook on combustion. They assume that all reactions go to completion, such that post combustion only unburned fuel/air and actual products remain. Assuming that combustion ...
7
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2answers
1k views

Heats of combustion and stability of rings

Can anyone explain why? If you think about it, without having the data of the heat of combustion of each type of bond, you can't really answer this question. I know that cyclopropane has a higher ...
4
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1answer
175 views

Heat of combustion for Octane

I'm a Mechanical Engineering student and I have been working on a school project but I want to go a bit beyond that and it has led me here. I'm designing an engine cylinder, and I figured I should be ...
8
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3answers
133 views

What really happens atomically in an explosion?

Let's say a room is filled with butane, I then throw a cigarette into the room. What happens to the atoms/molecules of the butane when they are in contact with the heat from the cigarette?
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1answer
190 views

Black Smoke Produced from Regular Lighter but Not Torch Lighter Applied to Copper

I have a piece of copper mesh from which I would like to remove all coatings/oils. The copper comes from a pot scrubber like this. In order to remove any residue, I held a standard bic lighter up to ...
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2answers
1k views

Why are methanol flames less visible than other flames?

The combustion of methanol tends to generate flames that are less visible than the flames generated by the combustion of other substances? My guess is that methanol burns quickly as it has a ...
2
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1answer
139 views

What is the mole fraction in mixture before combustion?

What is the mole fraction of $\ce{C2H6} / \ce{C3H8}$ in mixture, if both compounds reacted with $\ce{O2}$ in stoichiometric ratio? Mass of produced $\ce{CO2}$ is $1.819$ times larger than the mass of ...