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Thread: endothermic flame :?:

  1. #1 endothermic flame :?: 
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    hi

    i am interested in wither or not a cold flame is possable, i concluded that were it possable the flame would have to be endothermic (takes in heat energy from its surroundings) and despite researching through all the books at home at my old school and my colledge i found nothing on the subject, and so i turned to the internet for gidance and all i found was many pages on the quenching of a flame using an endothermic reaction.

    thank you for any useful input on the matter.


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  3. #2  
    Forum Senior anand_kapadia's Avatar
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    Endothermic reaction takes placewhen the internal energy of the reactants is less than that of products. And in this procedure heat is absorbed from the surrounding and the temperature decreases. Yes it will give a cold flame.
    Is this your question.
    Correct me if i am going wrong.


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  4. #3  
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    No it's not possible. A flame is characterised by a combustion reaction which is exothermic enough to emit visible light. In an endothermic reaction there would be not enough energy for the electrons to be excited into a higher energy state therefore emit light.
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  5. #4  
    Forum Professor leohopkins's Avatar
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    Quote Originally Posted by Lucky
    No it's not possible. A flame is characterised by a combustion reaction which is exothermic enough to emit visible light. In an endothermic reaction there would be not enough energy for the electrons to be excited into a higher energy state therefore emit light.
    I Agree.
    The hand of time rested on the half-hour mark, and all along that old front line of the English there came a whistling and a crying. The men of the first wave climbed up the parapets, in tumult, darkness, and the presence of death, and having done with all pleasant things, advanced across No Man's Land to begin the Battle of the Somme. - Poet John Masefield.

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  6. #5  
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    oh... i realy wanted to see what one would look like, obviously (were it possable) it would go downwards... damn... well thank you all for you input.

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  7. #6  
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    on another forum it was sujested that as a flame consits of a gas heated as to excite the electrons that when they come back to ground state release photons of light, if it where posable to find a gas that could have its electrons excited whilst remaining at a low tmeprature this would be possable, i the suggested that-

    could the elcetrons be excited through a form of electrolisys? could a catilyst be used in a useful way to aid the exciteing of the electrons without a large increase in temprature.

    any ideas/sugestions?
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  8. #7  
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    yep its possible but it would no longer be classed as or look like a flame. A good example would be neon lights where electricity passes through noble gases in a tube causing ionisation and the emmision of lights. While it is not an endothermic reaction, the energy provided for ionization comes from electrical energy not heat, so the lights remain relatively cold.
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  9. #8  
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    true. but thats not interesting enough lol, i realy wanted to find a something that looks like a flame...
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  10. #9  
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    Interesting conclusions but I would have to agree that this seems to be an impossibility because as stated earlier it would lose characteristics as a flame.
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  11. #10  
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    i think everyone agrees that it is possible but will neither look or be classified as a flame
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  12. #11  
    Forum Senior anand_kapadia's Avatar
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    not a flame but just increasein temp. of surrounding environment.
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  13. #12  
    Forum Professor leohopkins's Avatar
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    Quote Originally Posted by Lucky
    yep its possible but it would no longer be classed as or look like a flame. A good example would be neon lights where electricity passes through noble gases in a tube causing ionisation and the emmision of lights. While it is not an endothermic reaction, the energy provided for ionization comes from electrical energy not heat, so the lights remain relatively cold.
    Yup we know that. My glow in the dark stars also produce light, but they do not set the fire alarms off. :?
    The hand of time rested on the half-hour mark, and all along that old front line of the English there came a whistling and a crying. The men of the first wave climbed up the parapets, in tumult, darkness, and the presence of death, and having done with all pleasant things, advanced across No Man's Land to begin the Battle of the Somme. - Poet John Masefield.

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