A 0.150 M solution of aspirin (acetylsalicylic acid, C9H8O4) is titrated with 0.20 M KOH(aq). Which pH indicator would be the best choice for this titration? Data: K₂ (aspirin) = 3.0 x 10-4 Indicator Methyl orange Alizarin Yellow R 3.1 4.4 pH range of colour change 10.2 12.0 Phenolphthalein Bromocresol purple 5.2 6.6 8.3 10.0

A 0.150 M solution of aspirin (acetylsalicylic acid, C9H8O4) is titrated with 0.20 M KOH(aq). Which pH indicator would be the best choice for this titration? Data: K₂ (aspirin) = 3.0 x 10-4 Indicator Methyl orange Alizarin Yellow R 3.1 4.4 pH range of colour change 10.2 12.0 Phenolphthalein Bromocresol purple 5.2 6.6 8.3 10.0

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter16: Applications Of Neutralization Titrations

Section: Chapter Questions

Problem 16.20QAP

See similar textbooks

Similar questions

Chitinase is a protein that breaks down chitin, a primary component of the cell wall in fungi, scales in fish and exoskeletons of arthropods. The activity of chitinase extracted from a plant was shown to be optimum at pH 5. You were tasked to prepare 300 mL of 150 mM buffer solution for further analysis of the extracted chitinase. REAGENTS Ka 2.5M Acetic acid Solid NaOAc•3H2O [136.08g/mol] 1.76 x 10-5 2.5M NH3 Solid NH4Cl [53.49g/mol] 5.6 x 10-10 2.5M Lactic acid Solid sodium lactate [112.06g/mol] 4.0 x 10-5 5 M HCl 5M NaOH What are the moles of the (1) acid and (2) base components, given the following reagents? What is the mass/volume of the components needed to prepare the buffer solution?
The SO2 present in air is mainly responsible for the phenomenon of acid rain. The concentration of SO2 can be determined by titrating against a standard permanganate solution as follows: 5SO2 + 2MnO4- + 2H2O ---> 5SO42- + 2Ms2 + 4H+ Calculate the number of grams of SO2 in a sample of air if 4.90mL of 0.00700M KMnO4 solution are required for the titration. Be sure your answer has the correct number of significant digits.
134 grams of potassium sorbate KCH3 (CH)4CO2 is fully dissolved in 100.00 mL of water, which is carefully transferred to a conical flask. Then 100.00 mL of 0.240 M HNO3 is added dropwise to this solution from a burette. Given: Ka (sorbic acid) = 1.7 × 1O^-5 Showing all your calculations and reasoning, determine the pH of the solution that results after the addition of all the acid mentioned above. Suppose that the titration continues. Determine the pH of the solution in the flask at theequivalence point
Calculate the molar solubility of calcium oxalate in a solution that has been buffered so that its pH is constant and equal to 4.00. Data: Kps of CaC2O4 = 1.7x10 -9 ; Ka1 of H2C2O4 = 5.60x10-2 and Ka2 = 5.42x10-5 . Use systematic treatment.
The protein content of wheat flour can be determined reasonably accurately by multiplying the percentage of nitrogen present by 5.7. A 2.06-g sample of flour was taken through a Kjeldahl procedure and the ammonia produced was distilled into a boric acid solution. If this solution required 34.70 mL of 0.174 N HCl for titration to the methyl red end point, what is the a) % Nitrogen and b) % protein in the flour? (Use 1:1 stoich ratio between N and HCl)
A 20.00 mL aliquot of lactic acid solution (HCH3H5O3) was titrated with 0.0980 M KOH(aq) using both an indicator and a pH meter. Ka (HCH3H5O3), is 1.38 x10-4. A total of 28.64 mL of 0.0980 M KOH(aq) was required to reach the equivalence point 1. Calculate the molarity of the lactic acid solution. 2. Calculate the pH of the lactic acid solution 3. Calculate the pH and [CH3H5O3-] at the half-equivalence point. 4. Calculate the pH at the equivalence point of the titration. 5. Suggest an appropriate indicator for titration. 6. Calculate the pH of the solution after 10.00 mL of 0.0980 M NaOH(aq) was added
A metal M forms a water-soluble hydroxide with a chemical formula of MOH. To determine whatM is, a student prepared 250.0 cm3 of MOH standard solution by dissolving 1.17 g of MOH in distilled water. Then the student titrated 25.0 cm3of the solution with 0.055 M H2SO4(aq) usingphenolphthalein as indicator. The titration was repeated several times and the mean titre was 18.85cm3.(a) Describe how the 250.0 cm3 of MOH standard solution was prepared. (b) (i) Calculate the molar mass of MOH. (ii) Determine what M is. (Relative atomic masses: H = 1.0, O = 16.0) THANKYOU!!!
Use the following experimental titration data to calculate the concentration of the acid being analysed. Observations: The initial solution of acetic acid (HC2H3O2) is clear and colourless. A few drops of phenolphthalein indicator are added to each sample. A dilute solution of sodium hydroxide (concentration 2.50 x 10-4 mol/L) is used as the titrant. As the mixture reaches the endpoint, flashes of pink colour are seen and the titrant is added drop by drop. The endpoint is reached when one drop of titrant turns the mixture a pale pink colour that does not fade.
What is the difference between alkalinity and buffering capacity?
A 25.0-mL aliquot of vinegar was diluted to 250 mL in a volumetric flask. Titration of 50.0-mL aliquots of the diluted solution required an average of 25.23 mL of 0.09041 M NaOH. Express the acidity of the vinegar in terms of the percentage (w/v) of acetic acid.
Determine the pH at the equivalence (stoichiometric) point in the titration of 38.83 mL of 0.262 M (CH3)2NH(aq) with 0.111 M HCl(aq). The Kb of (CH3)2NH is 5.4 x 10-4.
You have a solution that contains acetic acid, (CH3COOH or HAc). The concentration of acetic acid in the aqueous solution is 0.35 mol / dm3. Ka = 1.7378 x 10 ^ -5 M a. Calculate the pH of the solution. 15 cm 3 of the acetic acid solution was titrated with sodium hydroxide solution, NaOH (aq), at a concentration of 0.5 mol / dm3 b. Describe how you would proceed to perform a titration of an acid of unknown concentration. What information can be obtained from a titration, describe the different phases. c. How much NaOH will be added when the equivalence point occurs?