Answer to Question #134808 in Organic Chemistry for Brayen

Question

What is the pH of a solution containing 0.200 mol sodium acetate and 0.100 mol acetic acid dissolved in 100.0 mL of water, given that the pKa of acetic acid is 4.75?

This amino acid has an overall net charge of -1 at pH 8.5
Select one:
a. arginine
b. cysteine
c. histidine
d. lysine
e. proline

Answer 1

1

P^H = P^Ka + log ( concentration of sodium acetate / concentration of acetic acid ) .

P^H = 4.75 + log 0.2 /100 / 0.1 /100 = 4.75 + log2 = 4.75 + 0.301 = 5.051 Answer .

2.

Answer is" histidine " .