Home
Class 12
CHEMISTRY
The pK(a1) and pK(a2) of an amino acid a...

The `pK_(a1)` and `pK_(a2)` of an amino acid are 2.3 and 9.7 respectively. The isoelectric point of the amino acid is:

A

`8.0`

B

`7.0`

C

`6.0`

D

`3.0`

Text Solution

Verified by Experts

The correct Answer is:
C
The isoelectric point `(pI)` of an amino acid such as alanine is the average of `pK_(a1)` and `pK_(a2)`
`PI = (2.3 + 9.7)/(2) = 6.0`
Always remember that the isoelectric point of an amino acid is the average of `pKa` of the monocation and `pKa` of the dipolar ion.
Promotional Banner

Topper's Solved these Questions

  • BIOMOLECULES

    R SHARMA|Exercise Follow_up_ Test 10|15 Videos

  • BIOMOLECULES

    R SHARMA|Exercise Follow_up_ Test 11|10 Videos

  • BIOMOLECULES

    R SHARMA|Exercise Follow_up_ Test 8|8 Videos

  • AMINES

    R SHARMA|Exercise Archives|36 Videos

  • CHEMICAL KINETICS

    R SHARMA|Exercise Archives|39 Videos

Similar Questions

Explore conceptually related problems

Isoelectric Point OF Amino Acid

At the isoelectric point, amino acids are present as

The pKa values for the three acidic group P,Q,R are 4.3, 9.7 and 2.2 respectively, Calculate the isoelectric point of the amino acid?

The pK_(a) values of ionisable groups in lysine are 2.18, 8.95 and 10.79 respectively. Find isoelectric point of lysine.

In an amino acid, the carboxyl group ionises at pK_(a1) = 2.34 and ammonium ion at pK_(a2) = 9.60 . The isoelectric point of the amino acid is at pH

The pK_(a) value of acids A,B,C and D are 2.3,3.2,4 and 5 respectively . The strongest acid amonst them is