If 25.00 mL of 0.20 mol/L HCO2H(aq) is titrated with 0.20 mol/L NaOH(aq) (the titrant), determine the pH
a) befor titration began

b)after 10.00 mL of NaOH has been added

c) at the equivalence point

  1. 👍 0
  2. 👎 0
  3. 👁 195
asked by Bradely
  1. a) before titration begins. That is a 0.2 M solution of HCOOH.
    HCOOH ==> H^+ + HCOO^-

    (HCOOH) = 0.2-x
    (H^+) = x
    (HCOO^-) = x
    Ka = (H^+)(HCOO^-)/(HCOOH)
    Plug the above variables into Ka and solve for (H^+), then convert to pH.

    b) after 10.00 mL NaOH has been added.
    HCOOH + NaOH ==> HCOONa + H2O

    mols HCOOH initially = M x L = ??
    mols NaOH added = M x L = ??
    mols HCOONa formed = ??

    pH = pKa + log[(base)/(acid)]

    c)at the equivalence point. We have the salt HCOONa + H2O at the equivalence point.
    HCOO^- + HOH ==> HCOOH + OH^-
    Kb = Kw/Ka = (HCOOH)(OH^-)/(HCOO^-)
    (HCOOH) = x
    (OH^-) = x
    (HCOO^-) = 0.2 - x
    Plug into Kb and solve for x = (OH^-), then convert to pH.

    Post your work if you get stuck.
    Check my thinking. Check my work. Check my arithmetic.

    1. 👍 0
    2. 👎 0
    posted by DrBob222
  2. a) Ka = (H^+)(HCOO^-)/(HCOOH)
    = (x)(x)/(0.2-x)
    = (x^2) / 0.2 - x

    Next step please...I Hate these problems :P:)

    1. 👍 0
    2. 👎 0
    posted by Sarah

Respond to this Question

First Name

Your Response

Similar Questions

  1. Chemistry

    "An aqueous sodium borate solution is titrated to the second endpoint with 0.225 mol/l nitric acid in the presence of a suitable indicator. If an average of 12.6mL of titrant are required to reach the second endpoint for a 25.0 mL

    asked by Stuck on May 15, 2010
  2. CHEM

    Which of the following mixtures will result in the formation of a buffer solution when dissolved in 1.00 L of water? i) 0.50 mol NaOH and 0.50 mol HCl. ii) 0.50 mol NaCl and 0.25 mol HCl. iii) 0.50 mol NaF and 0.25 mol HF. iv)

    asked by B on July 23, 2010
  3. chemistry

    Which of the following mixtures will be a buffer when dissolved in a liter of water? a. 0.1 mol Ca(OH)2 and 0.3 mol HI b. 0.3 mol NaCl and 0.3 mol HCl c. 0.4 mol NH3 and 0.4 mol HCl d. 0.2 mol HBr and 0.1 mol NaOH e. 0.2 mol H3PO4

    asked by George2 on May 21, 2010
  4. biology

    suppose 23mL of NaOH was required. How much Carbonic Acid was neutralized? 1L of .01 NaOH contains ____ mol NaOH? lmL of .01 NaOH contains _____mol NaOH? 23mL of .01 NaOH contains _____ mol NaOH? 2 mol of NaOH react with 1 mol

    asked by Anonymous on October 5, 2010
  5. Chemistry

    Commercial vinegar was titrated with NaOH solution to determine the content of acetic acid, HC2H3O2. For 20.0 milliliters of the vinegar 26.7 milliliters of 0.600-molar NaOH solution was required. What was the concentration of

    asked by Sarah on May 23, 2007
  6. chemistry

    What mass of sodium hydroxide pellets must be poured into a waste drum containing 20.0 L o 3.0 mol/L sulphuric acid to completely neutralize the waste acid solution? Write a balanced chemical equation for this reaction. okay, so

    asked by julie on December 15, 2014
  7. Chemistry

    Hi Can someone please help me undersand how to get the answer to this question A 15.0 mL solution of 0.050 mol/L AgNO3 was titrated with 0.0250 mol/L NaBr in the cell SCE || titrated solution | Ag(s) Find the cell voltage for 10.0

    asked by James on April 26, 2010
  8. CHEMISTRY FOR DR. BOB or anyone else

    A hypothetical weak acid HA, was combined with NaOH in the following proportions: 0.20 mol HA, 0.08 mol NaOH. The mixture was then diluted to a total volume of 1L, and the pH measured. (a) If pH=4.80, what is the pKa of the acid

    asked by Delli on May 11, 2007
  9. Inorganic chemistry

    mol KHP = (0.7719g)(1 mol KHP/204.2g) = .0038mol Where are the moles of NaOH? I know that there are 0.02637 L of NaOH and I know M = mol/l I know there are 40g NaOH/mol NaOH There is 1 mol of NaOH in the balanced equation But I do

    asked by Steve on April 14, 2009
  10. Chemistry(Please check)

    Which of the following mixtures will be a buffer when dissolved in 1 liter of water? 0.10 mol Ba(OH)2 and 0.20 mol HCl 0.30 mol KCl and 0.30 mol HCl 0.40 mol NH3 and 0.40 mol HCl 0.20 mol HNO2 and 0.10 mol NaOH 0.20 mol HBr and

    asked by Hannah on April 8, 2012

More Similar Questions