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    • Thread Starter

    I have some chemistry homework,

    i missed the lesson on this subject so can anyone please help me with this question? it says; what is the balanced chemical equation for hydrocarbon to produce carbon dioxide and water?

    1. octane
    2. butane

    if you can help please do! thanks :-)



    C8H18 + O2 --> CO2 + H2O (NOT BALANCED)

    To balance this equation, firstly, look at the carbons on the left. How many do we need on the right? 8. CO2 is the only compound on the right that has carbon in it, so it would become...

    C8H18 + O2 --> 8CO2 + H2O (NOT BALANCED)

    We now need to balance for hydrogen. We have 18 on the left and 2 on the right, so it would become....

    C8H18 + O2 --> 8CO2 + 9H2O (NOT BALANCED)

    We can now balance for oxygen. We have 25 on the right (16 in CO2 and 9 in H2O), so we need to balance the left hand side this time. So it would become...

    C8H18 + 25/2 O2 --> 8CO2 + 9H2O


    C4H10 + 13/2O2 --> 4CO2 + 5H2O

    Hope this helped!
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