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    I have a couple of questions I'm stuck on about aspirin. Any help appreciated.

    During the making of aspirin, is an ester the functional group created?

    Also, I've been told to work out a theoretical yield of aspirin, using 3g of hydroxybenzoic acid, and4ml of ethanouc anhydride, so need to work out the moles. What is the usual concentration of ethanouc anhydride used for this experiment?

    Also, why is water added to the mixture after reflux, and what is the purpose of cooling using an ice bath? Does it help with crystallisation?

    Thanks for any help
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    (Original post by definite_maybe)
    I have a couple of questions I'm stuck on about aspirin. Any help appreciated.

    During the making of aspirin, is an ester the functional group created?
    Yes

    Also, I've been told to work out a theoretical yield of aspirin, using 3g of hydroxybenzoic acid, and4ml of ethanouc anhydride, so need to work out the moles. What is the usual concentration of ethanouc anhydride used for this experiment?
    Pure ethanoic anhydride, not a solution, you may want the density of the liquid.

    Also, why is water added to the mixture after reflux, and what is the purpose of cooling using an ice bath? Does it help with crystallisation?
    The water is added to separate the organic and inorganic components of the crude mixture.

    An ice bath is used to decrease the solubility of the desired product from the crystallisation solvent (higher temperatures = more soluble, lower temperatures = less soluble).
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    (Original post by EierVonSatan)
    Yes



    Pure ethanoic anhydride, not a solution, you may want the density of the liquid.



    The water is added to separate the organic and inorganic components of the crude mixture.

    An ice bath is used to decrease the solubility of the desired product from the crystallisation solvent (higher temperatures = more soluble, lower temperatures = less soluble).
    Thank you. I haven't been given the density of the liquid to work out the theoretical yield. If the density is 1.08 (from wiki :p:) , is the mass then 1.08*4, and then use this to work out moles?
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    (Original post by definite_maybe)
    Thank you. I haven't been given the density of the liquid to work out the theoretical yield. If the density is 1.08 (from wiki :p:) , is the mass then 1.08*4, and then use this to work out moles?
    Yep (the density is correct)
 
 
 
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