Chemistry

a) Calculate [H3O^+] in a 0.15M solution of benzonic acid, HC7H5O2(aq) having K of 6.4x10^-5.

b) Calculate the per cent ionization of the HC7H5O2.

I got..

A) 0.16M but i did it again and got 7.2M so i'm very stuck as to the very different answers i got.

B) 12.4% ionization.

  1. 👍 0
  2. 👎 0
  3. 👁 109
asked by Sarah
  1. If you missed A you probably missed B.
    Call benzoic acid HB, then
    ................HB ==> H^+ + B^-
    initial........0.15....0......0
    change..........-x......x.....x.
    equil........0.15-x.....x......x

    K = (H^+)(B^-)/(HB)
    Substitute and solve for x.

    %ion = [(H^+)/0.15]*100 = ?

    1. 👍 0
    2. 👎 0
    posted by DrBob222

Respond to this Question

First Name

Your Response

Similar Questions

  1. chem 12

    a) Calculate [H3O^+] in a 0.15M solution of benzonic acid, HC7H5O2(aq) having K of 6.4x10^-5. b) Calculate the per cent ionization of the HC7H5O2. I got.. Kb = [HC7H5O3][OH]/HC7H5O2 6.3x10^-5 x Kb =1.0x10^-14 Kb =

    asked by Sarah on October 11, 2011
  2. chemistry 12

    Calculate [H3O^-] in a 0.15M solution of benzoic acid, HC7H5O2(aq) having a Ka of 6.4 x 10^-5 I got. 6.4x10^-5=(x)(x)/0.15 6.4x10^-5= x^2/0.15 6.4x10^-5 x 0.15 = x^2 square root of 9.6x10^-6 = square root of x^2 x= 0.003098 The pH

    asked by shelly on October 13, 2011
  3. Chemistry

    Calculate the [H3O+] and pH of each polyprotic acid solution. (b) 0.116 M H3C6H5O7 I did part (a) just fine, but for some reason can't figure (b) out. Can someone help me with just the [H3O+] part to get me started? I already got

    asked by DeeDee on April 6, 2013
  4. chemistry

    What is the [C7H5O2−] in a solution which is 0.1283 M in HC7H5O2 and 0.1364 M in HBr? HC7H5O2(aq) + H2O(l) « C7H5O2−(aq) + H3O+(aq) Ka = 6.5000e-5

    asked by Andy on May 6, 2014
  5. chemistry

    1)A solution has a [OH-] of 5.2 x 10-4. What is the [H3O+] in the solution? 2) A 0.25 M solution of a monoprotic acid, HA, has a pH of 2.54. What is Ka for this acid? The dissociation of HA is: HA + H2O H3O+ + A- (Hint: write the

    asked by nicki on December 9, 2012
  6. AP Chemistry

    A buffer solution contains .4mol of formic acid, HCOOH and a .6mol of sodium formate, HCOONa, in 1L of solution. Ka of formic acid is 1.8 x 10^-4. a) calculate pH b) if 100ml of this buffer solution is diluted to a volume of 1L

    asked by Jessie on April 25, 2010
  7. Chemistry

    Just two more to check, thanks! 1) The pH of a 1.25 M solution of unknown monoprotic acid is 5.43. Determine the value of Ka for this acid. HX H+ + X-. (I obtain 1.0 x 10^-11) 2) Calculate the pH of a solution which is 0.73 M

    asked by Amanda on May 1, 2014
  8. Chemistry

    1. Calculate the pH of a buffer solution that contains 0.32 M benzoic acid (C6H5CO2H) and 0.17 M sodium benzoate (C6H5COONa). [Ka = 6.5 × 10-5 for benzoic acid] Round your answer to two places past the decimal. 2. A solution is

    asked by Erin on April 8, 2013
  9. Chemistry

    1. Calculate the pH of a buffer solution that contains 0.32 M benzoic acid (C6H5CO2H) and 0.17 M sodium benzoate (C6H5COONa). [Ka = 6.5 × 10-5 for benzoic acid] Round your answer to two places past the decimal. 2. A solution is

    asked by Erin on April 8, 2013
  10. Chemistry

    find the concentration of h3o in a .86mol/l solution of the weak acid H2O2 (kA=2.4x10-12)

    asked by Buck on May 31, 2016

More Similar Questions