Question

4. You add 0.0500 mol of acetic acid (pKa= 4.76) to a 250.0 mL volumetric ask. How many mL of 0.500 M NaOH should you add to make a bu er with pH =5.00?

A) 63.50 mL    B) 25.60 mL     C)     5.23 mL     D)   1.85 mL   E)    0.0635 mL

5. You have a 6.5X10^-7M solution of sodium formate (Na^+HCOO^-) in water. Formate ion is the conjugate base of formic acid (HCOOH). What is the charge balance for the solution?

A) [H3O+]=[HCOO-] B)   6.5x10^-7 M = [HCOOH] + [HCOO-] C) [Na+] + [H3O+]=[HCOO-] + [OH-] D) [Na+]=[OH] E) None of the above.

Answer 1