Reaction formula for nitromethane (2 Viewers)

[flapjack]

In the discussion respirators/gas masks, there were statements made that
a byproduct of nitromethane combustion is nitric acid (HNO3).

But, the reaction formula for nitromethane is:

4CH3NO2 + 3O2 → 4CO2 + 6H2O + 2N2

Which does not contain HNO3 as a by product. I assume that the HNO3
comes from incomplete combustion, but I have not been able to find a
reference for this.

Any ideas?

P.S. Nitric acid is nasty stuff, I got burned by 12 molar nitric acid in high
school.

 

[flapjack]

Oooops. nitromethane. Write it a hundred times, Tom.

 

[Tim5636sc]

"In spark-ignition engines exhaust gas from an internal combustion engine whose fuel includes nitromethane, contains nitric acid vapor, which when inhaled causes a muscular reaction making it impossible to breathe, and people exposed to it should wear a gas mask." according to the MSDS for Nitromethane....was the quote from Mr. Darr....

http://www.sciencelab.com/msds.php?msdsId=9927374

according to this MSDS, I can't find anything where Nitric Acid Vapor was a bi-product.....? Maybe it's another MSDS sheet?

 

[The Counterfeiter]

In the discussion respirators/gas masks, there were statements made that a byproduct of nitromethane combustion is nitric acid (HNO3).But, the reaction formula for nitromethane is:
4CH3NO2 + 3O2 → 4CO2 + 6H2O + 2N2
Which does not contain HNO3 as a by product. I assume that the HNO3
comes from incomplete combustion, but I have not been able to find a
reference for this. Any ideas?

VERY interesting question! Chemistry is an extremely complicated subject and 2N2 caught my interest. It appears to actually be 2N squared (don't know how to generate a superscript character) and is not a compound. Google search for "Chemical Formula 2N2" leads to some stuff that will make your head hurt.
But . . . I did find that 2N2 is also a combustion product of a gunpowder explosion!
What is the chemical equation for black powder? - Yahoo! Answers

I have heard that up to half of the nitromethane passing through the motor is unburned and acts as a cooling factor. That would certainly lend some credence to your incomplete combustion theory. One thing for sure — something is coming out of those pipes that is not carbon dioxide, water or the mysterious 2N2. Fun stuff!

 

[flapjack]

according to the MSDS for Nitromethane....was the quote from Mr. Darr....

http://www.sciencelab.com/msds.php?msdsId=9927374

according to this MSDS, I can't find anything where Nitric Acid Vapor was a bi-product.....? Maybe it's another MSDS sheet?

This is typical of most information I find on the web. Just enough information
to wet the appetite, but not enough to satiate. I am going to ask my old high
school chemistry teacher about this. He'll know the answer...

 

[bottom end]

okay I'm not too familiar with chemistry and don't know what ch3n02 means. What chemical elements does nitromethane consist of?

 

[Huge]

okay I'm not too familiar with chemistry and don't know what ch3n02 means. What chemical elements does nitromethane consist of?

Mike are you going to start making nitro in your basement? ha-ha

 

[flapjack]

okay I'm not too familiar with chemistry and don't know what ch3n02 means. What chemical elements does nitromethane consist of?

carbon (C), hydrogen (H), nitrogen (N) and oxygen (O) are the chemical elements that comprise nitromethane. One part carbon, three parts hydrogen, one part nitrogen and 2 parts oxygen all mixed up in a specific recipe.

It gets the name nitromethane because of the nitro group (NO2) tacked on to the the methane group (CH3). The methane group is really CH4, but one hydrogen has been stripped away for the NO2 group to bond to the molecule.

 

[flapjack]

VERY interesting question! Chemistry is an extremely complicated subject and 2N2 caught my interest. It appears to actually be 2N squared (don't know how to generate a superscript character) and is not a compound.

<snip>

I have heard that up to half of the nitromethane passing through the motor is unburned and acts as a cooling factor. That would certainly lend some credence to your incomplete combustion theory. One thing for sure — something is coming out of those pipes that is not carbon dioxide, water or the mysterious 2N2. Fun stuff!

2N2 is really 2 nitrogen elements bonded to another another. N2 denotes nitrogen bonded to nitrogen. You can use _ to denote a subscript. By the way, most of the air we breath consists of N2.

I have also heard of the 1:1 air fuel ratio instead of the normal 2:1, the purpose being for cooling.

 

[TF CREW]

okay I'm not too familiar with chemistry and don't know what ch3n02 means. What chemical elements does nitromethane consist of?

Nitromethane is produced industrially by treating propane with nitric acid at 350–450 °C. This exothermic reaction produces the four industrially significant nitroalkanes: nitromethane, nitroethane, 1-nitropropane, and 2-nitropropane. The reaction involves free radicals, including the alkoxyl radicals of the type CH3CH2CH2O., which arise via homolysis of the corresponding nitrite ester. These alkoxy radicals are susceptible to C-C fragmentation reactions, which explains the formation of a mixture of products.

 

[twostep]

Nitromethane is produced industrially by treating propane with nitric acid at 350–450 °C. This exothermic reaction produces the four industrially significant nitroalkanes: nitromethane, nitroethane, 1-nitropropane, and 2-nitropropane. The reaction involves free radicals, including the alkoxyl radicals of the type CH3CH2CH2O., which arise via homolysis of the corresponding nitrite ester. These alkoxy radicals are susceptible to C-C fragmentation reactions, which explains the formation of a mixture of products.

YEAH....what he said...
I'm surprised the rest of you weren't aware of nitrite ester homolysis

Outstanding, Sean. If only I had a clue. I'll just settle for knowing nitromethane is commercially produced by treating propane with nitric acid.

 

[bottom end]

Mike are you going to start making nitro in your basement. ha-ha

yeah just like Uncle Fester...

No, the reason I asked is because I read that it was made from nitric acid and propane. Just wanted to see if that was right.

 

[Nitrohelper]

...this MSDS, I can't find anything where Nitric Acid Vapor was a bi-product...

I don't believe that the MSDS sheet deals with the burning of Nitromethane,
same for the reaction calculation when burned with methanol ...
I was involved with a testing lab that ran "sniffers" in the exhaust pipe of a Nitro Burning engine...
They wanted to determine all of the waste products of combustion and their concentrations...
These tests were done by a Nitro manufacturer about ten years ago... the tests were done at idle and WOT...

 

[sdwarf36]

" something is coming out of those pipes that is not carbon dioxide, water or the mysterious 2N2. Fun stuff! "

If its on fire-its horsepower--if its liquid its dollar bills........

 

[flapjack]

I asked ye olde high school chemistry teacher. It will be interesting to see what Master Ed has to say...

 

[vegasnitro]

The formula is only valid for burning 100% nitro. Most tuners today are only tipping the can ~85% ... the rest being methanol. That could account for some of the discrepencies in what is coming out of the pipes. However, I think the fuel bypassing the combustion process and coming out of the pipes in gaseous form accounts for the eye-watering, sinus-clearing and throat burning-effect that we all love ...

 

[flapjack]

The formula is only valid for burning 100% nitro. Most tuners today are only tipping the can ~85% ... the rest being methanol. That could account for some of the discrepencies in what is coming out of the pipes. However, I think the fuel bypassing the combustion process and coming out of the pipes in gaseous form accounts for the eye-watering, sinus-clearing and throat burning-effect that we all love ...

Agree. But the heat of combustion is converting the unburnt nitro to nitric acid plus something else that is burnt off while exiting the pipes

 

[mick]

.......I'm surprised the rest of you weren't aware of nitrite ester homolysis......

not to be confused with Mrs. Ester Homolysis

aren't visible nitro flames at night superheated unburnt hydrogen?
or some form of hydrogen mixing with atmosphere and igniting?

don't ask about 'superheated' - just thought it sounded cool in sentence
(although i'm guessing heat may have something to do with it?)

 

[Nitrohelper]

...aren't visible nitro flames at night superheated unburnt hydrogen?....or some form of hydrogen mixing with atmosphere and igniting....

NO , thats another internet "story" that gets repeated every few months...
I signed a confidential non-discloser agreement to not state what bye products were released due to combustion of a 90% mixture , but I think it's okay to say what wasn't present...
The tests were run by chemical engineers to determine if their theories were correct...

 

[flapjack]

NO , thats another internet "story" that gets repeated every few months...
I signed a confidential non-discloser agreement to not state what bye products were released due to combustion of a 90% mixture , but I think it's okay to say what wasn't present...
The tests were run by chemical engineers to determine if their theories were correct...

If nitromethane is made by treating propane with nitric acid, I suspect the byproducts are really propane and nitric acid dissociated under heat in the headers. The propane would account for the blue flame.