Answer to Question #230753 in General Chemistry for Mambwe

Question

Arginine is an amino acid which has the following pKa values: pK1: 2.17, pK2: = 9.04, pKR = 12.48. Calculate the net charge of arginine at the pH value of 4.

Answer 1

pH = (pKa1 + pKa2)/2.

Therefore, pH=pKa=(pK1+pK2+pKR)/3

=(2.17+9.04+12.48)/3

pH=7.9

According to the below referencing material, the Arginine's net charge is +1

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