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    For titration of 2 functional group (R-CH2COONa and R-NH2) with HCl, wich one of them will be titrated first ?
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    (Original post by merieriem)
    For titration of 2 functional group (R-CH2COONa and R-NH2) with HCl, wich one of them will be titrated first ?
    Provided that you have equal concentrations and volumes of both primary amine and carboxylate ion and HCl in excess, my thinking would say the primary amine would be titrated first.

    Both compounds contain the alkyl side chain , so both alkyl groups would show positive inductive effect and so increase the electron density at the carboxylate group(on the carboxylate ion) and on the N atom (primary amine).

    However, the negative charge on the carboxylate group is delocalised so it would be harder for a oxygen atom on the carboxylate group to become protonated by HCl. In the primary amine, the high electron density is ON the N atom, so it has become a stronger base compared to the carboxylate ion.

    So the N atom in primary amine becomes more readily available for protonation by HCl (compared to carboxylate ion) by the lone pair of electrons in the N atom.

    Just to make sure, are the 2 compounds together in the same solution or are they in different solutions.
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    (Original post by merieriem)
    For titration of 2 functional group (R-CH2COONa and R-NH2) with HCl, wich one of them will be titrated first ?
    A little research into zwitterions will give you both your answer and the background understanding.
 
 
 
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