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    What are the difference (if any) between:
    1. Combustion
    2. Burning
    3. Heating
    4. Thermal Decomposition

    I got asked a question on a chemistry past paper, about a chemical compound being heated, and I had to form an equation for the reaction. I wasnt sure if it would be "compound + O2 = products" or "compound = products"? Please help.
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    (Original post by ResidentEvil)
    What are the difference (if any) between:
    1. Combustion
    2. Burning
    3. Heating
    4. Thermal Decomposition

    I got asked a question on a chemistry past paper, about a chemical compound being heated, and I had to form an equation for the reaction. I wasnt sure if it would be "compound + O2 = products" or "compound = products"? Please help.
    not too sure actually..but i think that combustion and burning are the same (in the presence of oxygen) compound + O2 = products..
    heating and thermal decompostion are the same..compound=products
    cant be too sure though, ask boygenius
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    boygenius plz help
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    Burning and combustion imply that the substance is being combined with oxygen in the air, so if you were to write an equation you'd need to include the oxygen atoms. Thermal decomposition and heating imply that HEAT is applied, and has nothing to do with combination with oxygen - eg Group II Carbonates decompose on heating, CaCO3 ---> CaO + CO2 - no need to include oxygen.
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    (Original post by mongoose)
    Burning and combustion imply that the substance is being combined with oxygen in the air, so if you were to write an equation you'd need to include the oxygen atoms. Thermal decomposition and heating imply that HEAT is applied, and has nothing to do with combination with oxygen - eg Group II Carbonates decompose on heating, CaCO3 ---> CaO + CO2 - no need to include oxygen.
    Ok, so if a question says:
    a compound A is burnt to produce product B, then A + O2 = B ?

    So I assume the word if they just say "burn" then it is directly associated with oxygen involved or else they would say "burn in the absence of air"?
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    (Original post by ResidentEvil)
    Ok, so if a question says:
    a compound A is burnt to produce product B, then A + O2 = B ?

    So I assume the word if they just say "burn" then it is directly associated with oxygen involved or else they would say "burn in the absence of air"?
    The word burning itself implies the involvement of oxygen/air - to 'burn something in the absence of air/oxygen' does not make sense because it's simply impossible to ignite anything without oxygen/air (think back to GCSE Science, the experiment with the candle in the bell jar??).

    You're doing OCR Chemistry, right? For HFHF you do Combustion Enthalpies - you don't need to write down the number of oxygen atoms when constructing cycles because it's assumed that all the oxygen you need comes from the air, ie it's in excess.
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    (Original post by ResidentEvil)
    What are the difference (if any) between:
    1. Combustion
    2. Burning
    3. Heating
    4. Thermal Decomposition

    I got asked a question on a chemistry past paper, about a chemical compound being heated, and I had to form an equation for the reaction. I wasnt sure if it would be "compound + O2 = products" or "compound = products"? Please help.
    1. Combustion means when a substance is burned in oxygen to give other products.
    2. This literally means to undergo combustion. - -
    3. Heating only means to give heat energy to a substance.
    4. Only heat is applied. No reaction with oxygen.
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    (Original post by ResidentEvil)
    What are the difference (if any) between:
    1. Combustion
    2. Burning
    3. Heating
    4. Thermal Decomposition

    I got asked a question on a chemistry past paper, about a chemical compound being heated, and I had to form an equation for the reaction. I wasnt sure if it would be "compound + O2 = products" or "compound = products"? Please help.
    Combustion is reaction with oxygen. Can be complete or incomplete in certain cases, depending on whether oxygen is in excess or not.

    Burning is the same, but a less accurate term, eg. "burning" also happens inside the sun which is fusion of hydrogen, although you may get away with using this word.

    Heating is just applying heat, it's completely different because you can ehat something where there is no oxygen upto 3000 K and it will not combust. Heating is confused with combusting because when something reaches the activation energy of the reaction between itself and oxygen, a reactive molecule in the air, it burns.

    Thermal decomposition is causing a reaction to happen by heating - eg. 2NaNO3 ---> 2NaNO2 + O2. This is definately not combustion.

    Hope this makes sense.
 
 
 
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