Sample 1 2 3 4 Sample Volume, mL 50.00 49.50 25.00 50.00 Ba(OH)2 Volume, mL 43.17 42.68 21.47 43.33 A 0.1475-M solution of Ba(OH)2 was used to titrate the acetic acid (60.05 g/mol) in a dilute aqueous solution. The above results were obtained. 1. Calculate the mean w/v percentage of acetic acid in the sample 2. Calculate the standard deviation for the results. 3. Calculate the 90% confidence interval for the mean. 4. At the 90% confidence level, could any of the results be discarded?

Sample 1 2 3 4 Sample Volume, mL 50.00 49.50 25.00 50.00 Ba(OH)2 Volume, mL 43.17 42.68 21.47 43.33 A 0.1475-M solution of Ba(OH)2 was used to titrate the acetic acid (60.05 g/mol) in a dilute aqueous solution. The above results were obtained. 1. Calculate the mean w/v percentage of acetic acid in the sample 2. Calculate the standard deviation for the results. 3. Calculate the 90% confidence interval for the mean. 4. At the 90% confidence level, could any of the results be discarded?

Appl Of Ms Excel In Analytical Chemistry

2nd Edition

ISBN:9781285686691

Author:Crouch

Publisher:Crouch

Chapter3: Statistical Tests With Excel

Section: Chapter Questions

Problem 6P

See similar textbooks

Similar questions

Assume that a sample of hard water contains 50. mg/L of Mg2+ and 150 mg/L of Ca2+, with HCO3 as the accompanying anion. What mass of CaO should be added to 1.0 L of this aqueous solution to precipitate all the Mg2+ and Ca2+ as CaCO3 and MgCO3? What is the total mass of the two solids formed?
28
1. A sample of pure sodium oxalate, Na2C2O4 , weighing 0.2856 g is dissolved in water, sulfuric acid is added, and the solution titrated at 70°C , requiring 45.12 mL of a KMNO4 solution. The end point is overrun and back-titration is carried out with 1.74 mL of a 0.1032 N solution of oxalic acid. Calculate the normality of the KMNO4 solution. Hint: A redox reaction is involed between oxalate and permanganate. Look at the changes in oxidation state by determining the balanced redox reaction: 5C20,2 + + 2MN2+ 2 Mn04 + 10H* → 10CO2 + 8H20
12. 3.000 g BaCl₂.H₂O (molar mass=244.263 g/mol) was added to a solution of 100 mL of 0.050 M Na₂CO3. BaCl₂ (aq) + Na₂CO3 (aq) → BaCO3 (s) + 2NaCl Ksp for BaCO3 = 1.1 x 10-¹5 Calculate the concentration of CO2 in the resulting solution. a) 5M b) 0.050 M c) 0.072 M d) 1.5 x 10-¹³ M e) 1.5 x 10-14 M
5) The solubility of BaCO3 is 24 mg/L at room temperature. a. What is the molar solubility and the Ksp of barium carbonate? b. The carbonate ion can react with water as follows: CO3² (aq) + H₂O (1) HCO3 (aq) + OH- (aq) Kb = 2.1 x 10-4 Write the reaction out from part a, add the two reactions together, and calculate the new K of the combined reaction. C. Using your K from part b, find the solubility of BaCO3 when the reaction in part b is also considered. Did the solubility increase or decrease from part a? Explain using Le Chatelier's Principle.
3. To 20,00 ml of 0,1250 mol/l solution of silver nitrate – 25,00 ml of 0,1000 mol/l solution of potassium thiocyanate were added. Calculate pAg of this mixture. pKs(AgSCN) = 11,97 Express numerical result with an accuracy of: Х,ХX
1 gram of AgCl (s) is added to flask containing 98.741mL of an unknown NaCl solution. The concentration of Ag + after being added is 3.28487x10 -10 and the final mass of AgCl (s) is 1 gram. Determine the molarity of the unknown NaCl solution. Then determine the mass of NaCl dissovled in the unknown NaCl solution.
1. Calcium in a sample solution is determined by atomic absorption spectroscopy (AAS). A stock solution of calcium is prepared by dissolving 1.834 g CaCl, 2H,0 in water and diluting to 1 litre. From this stock solution, the second stock solution is prepared by the dilution factor of 10. Three standard solutions of calcium are prepared from the second stock solution with the following dilution factor: 20 (first standard solution), 10 (second standard solution) and 5 (third standard solution). A blank solution is prepared as well. Absorbance signals of AAS are as follows: 1.5 (blank solution), 10.6 (first standard solution), 20.1 (second standard solution), 38.5 (third standard solution), 29.6 (sample solution). (Molar mass; Ca = 40.00 g mol-, CI = 35.45 g mol-, 0 = 16.00 g mol-', H = 1.00 g mol-1) a. Construct ONE (1) plot that could be used to represent the calibration curve. b. From the plot of Q1a, determine the amount of calcium in parts per million.
- Calculate the concerntration of NaOH in the solution provided.
A sample (50 mL) of a bottled water was added to a 100 mL volumetric flask and then diluted to the mark. From this stock solution, 50 mL was taken, added to a 100 mL volumetric flask and diluted to the mark. Final concentration of the serial dilution: 587.7161ppm. 1. what is the concentration in the original bottle (ppm)
Standardization of a sodium hydroxide (NaOH) solution against potassium hydrogen phthalate (KHP) yielded the following results: Mass of KHP, g Volume of NaOH, mL 0.7987 38.29 0.8365 38.96 0.8104 38.51 0.8039 38.29 MM KHP: 204.22 MM NaOH: 40.00 a. Calculate the mean molar concentration of sodium hydroxide. (First, compute the concentration of NAOH in each titration then compute for its mean/average value.) b. Calculate the standard deviation. Please provide solutions for your answers. If you have used your calculator for calculating for mean and standard deviation, you can just provide the formula with the values indicated.
Maganite is the leading brand for antacid to alleviate heartburn. Its active ingredient is a saturated solution of magnesium hydroxide (milk of magnesia) which neutralizes the sudden increase of H+ during heartburn. Its manufacturing company performed microtitration to simulate how the drug works upon intake.A 50.0 mL saturated solution was prepared. After filtering each solution, a 5.0 mL aliquot was transferred to a 25.0 mL Erlenmeyer flask and was titrated using pre-standardized 0.0320 M HCl which resembled the gastric acid. The endpoint was reached after the addition of 52.2 μL titrant.1. What is the concentration of hydroxide ions in the solution? Note: Use the scientific notation of 0.00012 = 1.2e-4 2. Determine s and Ksp of Mg(OH)2.Note: Use the scientific notation of 0.00012 = 1.2e-4