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QJEEM18Ch7284: JEE Main 2018 Chemistry - Class 12 JEEM18Ch7284 Solution: The predominant form of histamine present in human blood is (pK …
The predominant form of histamine present in human blood is (pKa, Histidine = 6.0)
Multiple Choice Options
- A https://ik.imagekit.io/novatra/photos/36aa4c28be3cca527a361c5d3a6cefafb31cc1cc69c6f879cae0a635c53eb793.webp
- B https://ik.imagekit.io/novatra/photos/a0f387c8b4738e34db16df6b51b9621ba8701be9a0320576321c86c73c40e723.webp
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Step-by-Step Verified Solution
Blood is slightly basic in nature as it's pH is around 7.4 .
In Histamine there is two basic centers
(1)
(2)
Where pKa of Aliphatic amino group is 9.4 and pKa of basic nitrogen of imidazole ring is 5.8.
As more pKa value means more basic, So, aliphatic amino group is more basic.
As pH of blood is 7.4 so pKa of blood is < 7.4. So,
So, Histamine in blood will become this :
In Histamine there is two basic centers
(1)
(2)
Where pKa of Aliphatic amino group is 9.4 and pKa of basic nitrogen of imidazole ring is 5.8.
As more pKa value means more basic, So, aliphatic amino group is more basic.
As pH of blood is 7.4 so pKa of blood is < 7.4. So,
So, Histamine in blood will become this :