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    q : "explain the meaning of spontaneous in a thermodynamic context"
    answer is positive delta S total (entropy)

    i thought the answer was enthalpy must be negative because its what shows the heat content of the reaction, what has entropy got to do with it????
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    its what you have learnt in u4 chemistry. Read your chemistry books and you will find the answer
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    You obviously haven't studied entropy, yet, or you would know.

    Endothermic reactions do take place, e.g. acid + sodium hydrogencarbonate. They happen as there is an increase in entropy - the effect of which is greater than the increase in enthalpy.
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    (Original post by Pigster)
    You obviously haven't studied entropy, yet, or you would know.

    Endothermic reactions do take place, e.g. acid + sodium hydrogencarbonate. They happen as there is an increase in entropy - the effect of which is greater than the increase in enthalpy.
    Ok but if the entropy was negative and and delta H postive it wouldnt happen.. So why is entropy considered the main factor???
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    There are two ways of working out spontaneity, Delta G is one way, but it looks like the way you will do is in terms of total entropy change - which includes enthalpy change in the calculation.
 
 
 
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