The PK_a of Acetic Acid, HC₂H₃O₂, Is 4

Multiple Choice

The pK_a of acetic acid, HC₂H₃O₂, is 4.76. A buffer solution was made using an unspecified amount of NaC₂H₃O₂ and 0.30 moles of acetic acid in enough water to make 1.50 liters of solution. Its pH was measured as 4.55. How many moles of NaC₂H₃O₂ were used?Hint: The opposite operation of log(x) is 10^x.

A) 0.10 mol
B) 0.18 mol
C) 0.30 mol
D) 0.37 mol
E) 0.49 mol