Question

Consider the following sequence for aspartic acid :
The pI (isoelectric point) of aspartic acid is :

• A. 1.88
• B. 3.65
• C. 5.74
• D. 2.77

Answer 1

Answer: (D)

$PH=\frac{p{K}_1+p{K}_2}{2}$
$=\frac{1.88+3.65}{2}$
$=\frac{5.53}{2}$
$=2.765\approx 2.77$
At Isoelectric point of Aspartic Acid both carboxylic as well as amino from co-exist.