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    The question said :

    State the name given to the enthalpy change represented by the following chemical equation..

    C(s) + 1/2 O2 -----> CO(g)


    The anwser is, standard enthalpy of formation.

    I just don't see why or how?
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    Standard enthalpy of formation goes like enthalpy change when a substance is formed for its element under standard condition 298k 100kpa and we see nothing else except carbon monoxide formed from its element

    If it was combustion CO2 + H20 would be formed
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    The definition for Enthalpy of formation is:
    The standard enthalpy of formation is defined as the change in enthalpy when one mole of a substance in the standard state (1 atm of pressure and 298.15 K) is formed from its pure elements under the same conditions.
    (Source: http://chemwiki.ucdavis.edu/Core/Phy...y_Of_Formation)

    Which means that carbon is a pure element and so is oxygen. 1 mole of carbon monoxide is formed so this is a standard enthalpy of formation (if it occurs under standard state ofc).
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    (Original post by X_alwayssmiley)
    The question said :

    State the name given to the enthalpy change represented by the following chemical equation..

    C(s) + 1/2 O2 -----> CO(g)


    The anwser is, standard enthalpy of formation.

    I just don't see why or how?
    The definition of enthalpy of formation is the energy change when 1 mole of the compound from its constituent elements (in their molar quantities). Look at the equation - notice that CO is formed from C and O2
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    (Original post by kiiten)
    The definition of enthalpy of formation is the energy change when 1 mole of the compound from its constituent elements (in their molar quantities). Look at the equation - notice that CO is formed from C and O2
    OH ! I see it now, thank you so much!
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    (Original post by X_alwayssmiley)
    OH ! I see it now, thank you so much!
    You're welcome
 
 
 
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