Amino Acid Protonation

Which one is the zwitterion form of alanine?

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• 

Alanine has two pKa (2.35, 9.87). Which one is the major form at alanine at pH = 6?

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• 

Alanine has two pKa (2.35, 9.87). What is the net charge of alanine at pH = 11?

• 0

• -1

• +1

Aspartic acid has an acidic side chain. The pKa of main chain and side chain COOH are 2.10 and 3.86 respectively. Which one is the major form of aspartic acid at pH = 3?

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• 

Lysine has a basic side chain. The pKa for the main chain and side chain -NH2 are 8.95 and 10.53 respectively. Which one is the major form of lysine at pH = 10?

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• 

Tags

NGSS.HS-PS1-5

The pKa for glutamic acid -COOH, -NH2 and side chain are 2.10, 9.47 and 4.07 respectively. What is the pH at the isoelectric point of glutamic acid?

• 3.08

• 6.77

• 5.19

The pKa for lysine -COOH, -NH2, and side chaine (-NH2) are 2.18, 8.95, and 10.53 respectively. What is the pH at the isoelectric point of lysine?

• 5.56

• 9.74

• 6.35

Tags

NGSS.HS-LS1-6

Glutamine has two pKa (2.17 and 9.13). Which one is the major form of glutamine at pH = 1.5?

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• 

Which part of the titration curve is the isoelectric point of alanine?

• II

• III

This titration curve is likely to be ..

• glycine

• glutamic acid

• lysine

Tags

NGSS.HS-PS1-2