A Student Wants to Make a PH 4

question 19

Multiple Choice

A student wants to make a pH 4.0 buffer solution. She decides to use a buffer made from formic acid and sodium formate (NaCOOH) . She adds 50.0 grams of sodium formate to a 1 L volumetric flask. How many mL of 3.0 M formic acid should she add to the 1 L volumetric flask so that when the flask is diluted to the mark the pH will be 4.00?

• A) 13.8 ml
• B) 138 ml
• C) 72.6 ml
• D) 726 ml
• E) None of the above