Post a New Question

Chemistry Lab

posted by .

A 15.00 mL sample of a weak acid with Ka = 3.52x10-4, was titrated with 0.475 M KOH. The equivalence point was reached after addition of 19.5 mL of KOH with the phenolphthalein indicator. Determine the molar concentration of the original acid solution, then find pH and a % ionization of the acid in the original solution.

How do I set up this problem? I don't know where to start.

  • Chemistry Lab -

    HA + NaOH ==> NaA + H2O
    mols NaOH = M x L = ?
    mols HA = mols NaOH (look at the equation. 1 mol HA = 1 mol NaOH)
    M HA = mols HA/L HA.

    .........HA ==> H^+ + A^-
    I........?M......0......0
    C.........-x.....x.......x
    E........?M -x...x.......x

    Ka = (H^+)(A^-)/(HA)
    Substitute and solve for (H^+) and convert to pH. pH = -log(H^+).

    Finally, %ion = [(H^+)/M]*100 = xx

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Chemistry Titration Lab HELP!

    Hi everyone! I just got a new lab that I MUST complete today, and it's about titration- I have absolutely no clue how to do it, it just doesn't make sense to me! I hope that someone can help explain to me how to do it so I can finish …
  2. college chemistry

    Consider the titration of a 50.0 mL sample of a 0.100 M solution of the triprotic weak acid citric acid (H3C6H5O7) with 0.100 M KOH. For citric acid, the three (3) acid dissociation constant values are ka1 = 7.40x10-3, ka2 = 1.70x10-5, …
  3. chemistry

    1) a 100ml smaple of 0.18M HCLO4 is titrated with 0.27M LiOH. determine the ph of the soution after the addition of 66.67 ml of LiOH (this is at equivalence point) 2)a 100 ml sample of .20M HF is titrated with .10M KOH. determine th …
  4. Chemistry

    A student titrates 0.100M KOH into 50.00 ml of weak acid HX. The pH of the solution is 4.25 after 20.00 ml of the base has been added, and equivalence point is reached when 40.00 ml of the base is added. 1. What is the concentration …
  5. Chemistry

    A student titrates 0.025 M KOH into 50.00 ml of a solution of unknown weak acid HA. Equivalence point is reached when 30.00 ml of the KOH has been added. After 15.00ml of the KOH has been added the pH of the mixture is 3.92. A. What …
  6. Chemistry

    A student titrates 0.025 M KOH into 50.00 ml of a solution of unknown weak acid HA. Equivalence point is reached when 30.00 ml of the KOH has been added. After 15.00ml of the KOH has been added the pH of the mixture is 3.92. A. What …
  7. Chemistry

    A titration is performed by adding .600 M KOH to 40.0 mL of .800 M HCl. Calculate the pH before addition of any KOH. Calculate the pH after the addition of 5.0 mL of the base. Calculate the volume of base needed to reach the equivalence …
  8. Chemistry

    A 50.0 mL sample of 0.23 M propanoic acid, CH3CH2COOH, a weak monoprotic acid, is titrated with 0.14 M KOH. Ka of CH3CH2COOH = 1.4 multiplied by 10-5. What is the pH at equivalence point?
  9. chemistry

    0.5 L of a 0.30 M HCl solution is titrated with a solution of 0.6 M KOH. a)What is the pH before addition of KOH?
  10. chemistry

    a 30.0ml sample of diprotic acid is titrated with .260M KOH. if 68.5ml is required to reach the equivalence point, what is the concentration of the acid?

More Similar Questions

Post a New Question