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for oligopeptide Val-Lys-Met-Tyr-Glu-Ser. sketch the tittation curve frim 0-14 ph y axis vs 5 equvalents of...

for oligopeptide Val-Lys-Met-Tyr-Glu-Ser. sketch the tittation curve frim 0-14 ph y axis vs 5 equvalents of KOH
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The given oligopeptide Val-Lys-Met-Tyr-Glu-Ser, is composed with acidic glutamic acid or glutamate (Glu), basic lysine (Lys) and four neutral Valine (Val), methionine (Met), tyrosine (Tyr) and Serine (Ser) amino acids.

Hence, since this oligopeptide has been titrated with 5 equivalents of KOH, only its acidic part i.e. glutamic acid (Glu) part will be neutralized or will be titrated.

So, it would definitely follow the weak acid and strong base path of titration. For 5 equivalents of KOH, the normality(N) of the KOH solution is 5 N.

But in this question, I believe some very important data are missing, like pka1, pka2 and pka3 (for acidic or basic) values of the amino acids are missing. The concentration or thev weight of the oligopeptide isn't given (so, how can I calculate the pH of the solution at different steps of the titration). Again, the biggest problem in this question is, the question demand the titration plot of pH (Y-axis) vs 5 equivalents of KOH (X-axis), in this case since the X-axis has only one value, I'm afraid it can't be plotted... More importantly, in practical aspect, the base (i.e. KOH here) should be added dropwise and generally we plot pH vs the volume of base or acid is added... So, please modify the question so that I can answer it properly.

There is many parameters aren't given and even the question seems to be wrong. So, I can't answer properly.

But, yes as it is weak acid vs strong base titration, and if I consider (a) the base, KOH is added from burette and (b) still the concentration or amount of the peptide has to be given, if I consider it is same as the base; Initially, when there is no base has been added i.e. at volum (V) = 0 ml, the pH = pH of the glutamic acid and after this, it gradually increases and the end point might be come at pH of 6-11 (If, concentration are given it can be calculated exactly). Finally after this it increases more as now the solution is become basic, if you add more and more base, finally it would be reached to pH = 14.

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