Chem

posted by .

A buffer contains 1.0mol CH3CO2H and 1.0mol CH3CO2^- diluted with water to 1.0L. How many moles of NaOH are required to increase the pH of the buffer to 5.10? (pKa oof Ch3CO2H=4.74)

  • Chem -

    You want to use the Henderson-Hasselbalch equation,
    pH = pKa + log (base/acid)
    First, plug in 5.10 for pH and 4.74 for pKa, and solve the H-H equation for B/A ratio.

    Then look at the equation if you add OH^- to the buffer solution. It will neutralize acid to produce more acetate at the expense of CH3COOH.
    CH3COOH + OH^- ==> CH3COO^- HOH

    Here is what I would do.
    Let x = moles OH^- to be added which is what the problem asks for.
    You are starting with 1 mole CH3COOH and 1 mole CH3COO^-
    At the end of x moles OH^-, the concns are
    1-x for CH3COOH (acid) and 1+x for CH3COO^- (base).
    Now plug those into the B/A you solved for above and solve for x.
    Then to make sure you are right, plug B and A back into the H-H equation and see if you end up with pH of 5.01. Post your work if you get stuck. It may sound complicated but it really is straight forward.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. CHEMISTRY

    A BUFFER SOLUTION IS MADE FORM 0.10 MOLES NaF AND 0.25 MOLES OF HF IN 1 LITER OF WATER ----WHAT WILL THE BUFFER CAPACITY BE IF 1.0M HCL IS ADDED -----WHAT IF 2.0 M OF NAOH IS ADDED?
  2. chemistry

    a buffer composed of 0.50mol acetic acid and 0.50mol sodium acetate is diluted to a volume of 1.0L. The pH of the buffer is 4.74. How many moles of NaOH must be added to the buffer solution to increase its pH to 5.74?
  3. Chemistry

    Calculate the molar concentration of H+ ion of a solution that is 3.45×10-1 M in CH3CO2H and 1.62×10-3 M in the salt CH3CO2Li. CH3CO2H(aq) = CH3CO2-(aq) + H+(aq)
  4. Buffer L

    CH3CO2H: 0.109M & 20ml NaOH : 0.109M& 10ml H20:10ml Buffer Problem, when I solve it the ratio becomes the same and the pH is the same as the pka, is that right?
  5. chemistry

    Calculate the [CH3CO2H] in a solution if it has a pH 3.21. CH3CO2H = CH3CO2- + H+
  6. Chemistry

    A buffer contains 0.50 mol CH3CO2H and 0.50 mol CH3CO2- diluted with water to 1.0 L. How many moles of NaOH are required to increase the pH of the buffer to 5.00?
  7. Chemsitry

    What is the pH of the buffer solution that results when 58.50 g of sodium acetate (NaCH3CO2) (Formula Mass = 82.02 g mol-1) is added to 1 litre of 0.45 mol L-1 acetic acid (CH3CO2H) ?
  8. chemistry

    Pka of Ch3CO2H is 4.75 What is the equilibrium constant of the equation: Ch3Co2 (aq) + H20 (l) --> CH3CO2H(aq) + OH-(aq)
  9. chemistry

    What is the pH of a buffer solution that has CH3CO2H=0.68 M and CH3CO2- =0.58 M, and has 0.01 M concentration of H2SO4 added to it?
  10. Chemistry

    A buffer system contains 0.30 M NH4+ and 0.15 M NH3. pKa of NH4+ is 9.25. How many moles of NaOH must be added to 1.00 L of this solution to increase the pH to 9.25?

More Similar Questions