1. Tardigrade
  2. Question
  3. Chemistry
  4. Paragraph 2 An amino acid reacts with 10 ml 0.05 M NaOH and the final solution has pH =2.30. When 20 ml of the same base is added in the resulting solution, the pH becomes 9.7. Identify the amino acid and calculate the isoelectric point of the amino acid. This amino acid is prepared by the reaction of compound (X) with NH 3 and further hydrolysis with HCN. Compound (X) is less C atom containing compound that gives positive iodoform test and positive Fehling's solution test. Isoelectric point of the amino acid is:

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Q. Paragraph 2
An amino acid reacts with $10\, ml 0.05\, M\, NaOH$ and the final solution has $pH =2.30$. When $20\, ml$ of the same base is added in the resulting solution, the $pH$ becomes $9.7$. Identify the amino acid and calculate the isoelectric point of the amino acid. This amino acid is prepared by the reaction of compound (X) with $NH _{3}$ and further hydrolysis with $HCN$. Compound (X) is less $C$ atom containing compound that gives positive iodoform test and positive Fehling's solution test.
Isoelectric point of the amino acid is:

Amines

Solution:

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When partial neutralisation of alanine occurs,
Then, $pH = p K_{ a }+\log \left[\frac{\text { salt }}{\text { acid }}\right]$
[salt]=[acid]
$pH _{1}= p _{ a 1}$ and $pH _{2}= p _{ a 2}$
$\therefore pH =\frac{ p _{ a _{1}}+ p _{ a _{2}}}{2}$
$=\frac{9.7+2.3}{2}=\frac{12.0}{2}=6.0$