Question: Assuming a large number of measurements so

> Construct a curve for the titration of 50.00 mL of a 0.1000 M solution of compound A with a 0.2000 M solution of compound B in the following table. For each titration, calculate the pH after the addition of 0.00, 12.50, 20.00, 24.00, 25.00, 26.00, 37.50,

> Changes in the method used to coat the tablets in Problem 6-6 lowered the percentage of rejects from 8.0% to 3.0%. How many tablets should be taken for inspection if the permissible relative standard deviation in the measurement is to be a. 15%?

> Briefly explain why curve B cannot describe the titration of a mixture consisting of H3PO4 and NaH2PO4.

> Describe the composition of a solution that would be expected to yield a curve resembling (see Problem 13-26) a. curve B. b. curve A. c. curve E.

> Identify by letter the curve you would expect in the titration of a solution containing a. Disodium maleate, Na2M, with standard acid. b. Pyruvic acid, HP, with standard base. c. Sodium carbonate, Na2CO3, with standard acid.

> The solubility products for a series of iodides are List these four compounds in order of decreasing molar solubility in (a) water. (b) 0.20 M NaI. (c) a 0.020 M solution of the solute cation.

> How would you prepare 1.00 L of a buffer with a pH of 6.00 from 0.500 M Na3AsO4 and 0.400 M HCl?

> How would you prepare 1.00 L of a buffer with a pH of 7.00 from 0.200 M H3PO4 and 0.160 M NaOH?

> Ammoniacal nitrogen can be determined by treatment of the sample with chloroplatinic acid; the product is slightly soluble ammonium chloroplatinate: The precipitate decomposes on ignition, yielding metallic platinum and gaseous products: Calculate the pe

> How would you prepare 1.00 L of a buffer with a pH of 9.45 from 0.300 M Na2CO3 and 0.200 M HCl?

> What is the pH of the buffer formed by adding 100 mL of 0.150 M potassium hydrogen phthalate to a. 100.0 mL of 0.0800 M NaOH? b. 100.0 mL of 0.0800 M HCl?

> . What is the pH of the buffer formed by mixing 50.0 mL of 0.200 M NaH2PO4 with a. 50.0 mL of 0.100 M HCl? b. 50.0 mL of 0.100 M NaOH?

> What mass (g) of dipotassium phthalate must be added to 750 mL of 0.0500 M phthalic acid to give a buffer of pH 5.75?

> A coating that weighs at least 2.00 mg is needed to impart adequate shelf life to a pharmaceutical tablet. A random sampling of 200 tablets revealed that 16 failed to meet this requirement. a. Use this information to estimate the relative standard deviat

> What mass (g) of Na2HPO4 . 2H2O must be added to 750 mL of 0.160 M H3PO4 to give a buffer of pH 7.30?

> Identify the principal conjugate acid-base pair and calculate the ratio between them in a solution that is buffered to pH 9.00 and contains a. H2S. b. ethylenediamine dihydrochloride. c. H3AsO4. d. H2CO3.

> Identify the principal conjugate acid-base pair and calculate the ratio between them in a solution that is buffered to pH 6.00 and contains a. H2SO3. b. Citric acid. c. Malonic acid. d. Tartaric acid.

> Calculate the pH of a solution that is a. 0.0100 M in HClO4 and 0.0300 M in monochloroacetic acid. b. 0.0100 M in HCl and 0.0150 M in H2SO4. c. 0.0100 M in NaOH and 0.0300 M in Na2S. d. 0.0100 M in NaOH and 0.0300 M in sodium acetate.

> What is the mass in grams of solute in a. 250 mL of 0.264 M H2O2? b. 37.0 mL of 5.75 × 10-4 M benzoic acid (122 g/mol)? c. 2.50 L of a solution that contains 37.2 ppm of SnCl2? d. 11.7 mL of 0.0225 M KBrO3?

> The iodide in a sample that also contained chloride was converted to iodate by treatment with an excess of bromine: The unused bromine was removed by boiling; an excess of barium ion was then added to precipitate the iodate: In the analysis of a 1.59-g

> Calculate the pH of a solution that is a. 0.0100 M in HCl and 0.0200 M in picric acid. b. 0.0100 M in HCl and 0.0320 M in benzoic acid. c. 0.0100 M in NaOH and 0.075 M in Na2CO3. d. 0.0100 M in NaOH and 0.090 M in NH3.

> Calculate the pH of a solution that contains the following analytical concentrations: a. 0.225 M in H3PO4 and 0.414 M in NaH2PO4. b. 0.0670 M in Na2SO3 and 0.0315 M in NaHSO3. c. 0.640 M in HOC2H4NH2 and 0.750 M in HOC2H4NH3Cl. d. 0.0240 in H2C2O4 (o

> Calculate the pH of a solution that contains the following analytical concentrations: a. 0.0200 M in H3PO4 and 0.0500 M in NaH2PO4. b. 0.0300 M in NaH2AsO4 and 0.0500 M in Na2HAsO4. c. 0.0400 M in Na2CO3 and 0.0500 M in NaHCO3. d. 0.0400 M in H3P

> Calculate the pH of a solution that is 0.0400 M in a. Na3PO4. b. Na2C2O4. c. Na2HPO3. d. Na2SO3. e. Na2S. f. C2H4(NH3 1CI2)2.

> Calculate the pH of a solution that is 0.0400 M in a. NaH2PO4. b. NaHC2O4. c. NaH2PO3. d. NaHSO3. e. NaHS. f. H2NC2H4NH3 +CI-.

> The following results were obtained for the determination of calcium in a NIST limestone sample: %CaO = 51.33, 51.22, 51.36, 51.21, and 51.44. Five gross samples were then obtained for a carload of limestone. The average percent CaO values for the gross

> Calculate the pH of a solution that is 0.0400 M in a. H3PO4. b. H2C2O4. c. H3PO3. d. H2SO3. e. H2S. f. H2NC2H4NH2.

> Suggest a suitable indicator for a titration based on each of the following reactions. Use 0.05 M if an equivalence point concentration is needed. a. H2CO3 + NaOH→ NaHCO3 + H2O b. H2P + 2NaOH → Na2P + 2H2O (H2P 5 o@phthalic acid) c. H2T + 2NaOH → Na2

> Suggest a method for determining the amounts of H3PO4 and NaH2PO4 in an aqueous solution.

> Suggest an indicator that would give an end point for the titration of the first two protons in H3AsO4.

> The mercury in a 1.0451-g sample was precipitated with an excess of paraperiodic acid, H5IO6: The precipitate was filtered, washed free of precipitating agent, dried, and weighed, and 0.5718 g was recovered. Calculate the percentage of Hg2Cl2 in the sa

> Why are the standard reagents used in neutralization titrations generally strong acids and bases rather than weak acids and bases?

> The solubility-product constant for K2PdCl6 is What is the K1 concentration of a solution prepared by mixing 50.0 mL of 0.200 M KCl with 50.0 mL of a. 0.0800 M PdCl62-? b. 0.160 M PdCl62-? c. 0.240 M PdCl62-?

> Consider curves for the titration of 0.10 M NaOH and 0.010 M NH3 with 0.10 M HCl. a. Briefly account for the differences between curves for the two titrations. b. In what respect will the two curves be indistinguishable?

> What factors affect end-point sharpness in an acid-base titration?

> Why does the typical acid-base indicator exhibit its color change over a range of about 2 pH units?

> Supply the missing data in the following table.

> What factors determine the mass of a gross sample?

> Calculate the molar concentration of a solution that is 50.0% NaOH (w/w) and has a specific gravity of 1.52..

> Calculate the equilibrium concentration of methyl ammonia in a solution that has a molar analytical CH3NH2 concentration of 0.120 and a pH of 11.471.

> Calculate a0 and a1 for a. Acetic acid in a solution with a ph of 5.320. b. Picric acid in a solution with a ph of 1.750. c. Hypochlorous acid in a solution with a ph of 7.00. d. Hydroxylamine acid in a solution with a ph of 5.54. e. Piperidine in a solu

> Five different laboratories participated in an interlaboratory study involving determinations of the iron level in water samples. The following results are replicate determinations of Fe in ppm for laboratories A through E. a. State the appropriate hypot

> Calculate the pH after addition of 0.00, 5.00, 15.00, 25.00, 40.00, 49.00, 50.00, 51.00, 55.00, and 60.00 mL of reagent in the titration of 50.0 mL of a. 0.01000 M chloroacetic acid with 0.01000 M NaOH. b. 0.1000 M anilinium chloride with 0.1000 M NaO

> Calculate the pH after addition of 0.00, 5.00, 15.00, 25.00, 40.00, 45.00, 49.00, 50.00, 51.00, 55.00, and 60.00 mL of 0.1000 M HCl in the titration of 50.00 mL of a. 0.1500 M ammonia. b. 0.1500 M hydrazine. c. 0.1500 M sodium cyanide.

> Calculate the pH after addition of 0.00, 5.00, 15.00, 25.00, 40.00, 45.00, 49.00, 50.00, 51.00, 55.00, and 60.00 mL of 0.1000 M NaOH in the titration of 50.00 mL of a. 0.1000 M HNO2. b. 0.1000 M pyridinium chloride. c. 0.1000 M lactic acid.

> What is the mass in milligrams of solute in a. 16.0 mL of 0.350 M sucrose (342 g/mol)? b. 1.92 L of 3.76 × 10-3 M H2O2? c. 356 mL of a solution that contains 2.96 ppm of Pb (NO3)2? d. 5.75 mL of 0.0819 M KNO3?

> Briefly describe or define and give an example of a. An amphiprotic solvent. b. A differentiating solvent. c. A leveling solvent. d. A mass-action effect.

> In a titration of 50.00 mL of 0.1000 M ethylamine with 0.1000 M HClO4, the titration error must be no more than 0.05 mL. What indicator can be chosen to realize this goal?

> In a titration of 50.00 mL of 0.05000 M formic acid with 0.1000 M KOH, the titration error must be smaller than 0.05 mL. What indicator can be chosen to realize this goal?

> Before agreeing to the purchase of a large order of solvent, a company wants to see conclusive evidence that the mean value of a particular impurity is less than 1.0 ppb. What hypotheses should be tested? What are the type I and type II errors in this si

> A 50.00-mL aliquot of 0.1000 M NaOH is titrated with 0.1000 M HCl. Calculate the pH of the solution after the addition of 0.00, 10.00, 25.00, 40.00, 45.00, 49.00, 50.00, 51.00, 55.00, and 60.00 mL of acid, and prepare a titration curve from the data.

> A 5.500-g sample of a pesticide was decomposed with metallic sodium in alcohol, and the liberated chloride ion was precipitated as AgCl. Express the results of this analysis in terms of percent DDT 1C14H9Cl52 based on the recovery of 0.1873 g of AgCl.

> Calculate the change in pH to three decimal places that occurs when 0.50 mmol of a strong acid is added to 100 mL of a. 0.0100 M lactic acid 1 0.0800 M sodium lactate. b. 0.0800 M lactic acid 1 0.0200 M sodium lactate. c. 0.0500 M lactic acid 1 0.0500

> Calculate the change in pH that occurs when 1.50 mmol of a strong base is added to 100 mL of the solutions listed in Problem 12-34. Calculate values to three decimal places.

> Calculate the change in pH that occurs when 1.00 mmol of a strong acid is added to 100 mL of the solutions listed in Problem 12-3

> Calculate the change in pH that occurs in each of the following solutions as a result of a tenfold dilution with water. Round calculated values for pH to three figures to the right of the decimal point. a. H2O b. 0.0500 M HCl c. 0.0500 M NaOH d. 0.

> What is the pH of a solution that is a. Prepared by dissolving 3.30 g of 1NH422SO4 in water, adding 125.0 ml of 0.1011 M naoh, and diluting to 500.0 ml? b. 0.120 M in piperidine and 0.010 M in its chloride salt? c. 0.050 M in ethylamine and 0.167 M in it

> What is the pH of a solution that is a. Prepared by dissolving 6.75 g of lactic acid (90.08 g/mol) and 5.19 g of sodium lactate (112.06 g/mol) in water and diluting to 1.00 L? b. 0.0430 M in acetic acid and 0.0175 M in sodium acetate? c. Prepared by diss

> A solution is 0.0500 M in NH4Cl and 0.0300 M in NH3. Calculate its OH-concentration and its pH a.Neglecting activities. b.Taking activities into account.

> The solubility-product constant for Ce(IO3)3 is 3.2 × 10-10. What is the Ce3+ concentration in a solution prepared by mixing 50.00 mL of 0.0500 M Ce3+with 50.00 mL of a. Water? b. 0.0500 M IO3-? c. 0.250 M IO3-? d. 0.0450 M IO3-?

> Calculate the pH of the solution that results when 20.0 mL of 0.2500 M NH3 is a.Mixed with 20.0 ml of distilled water. b.Mixed with 20.0 ml of 0.250 M hcl solution. c.Mixed with 20.0 ml of 0.300 M hcl solution. d.Mixed with 20.0 ml of 0.200 M NH4Cl solut

> Describe in your own words why the confidence interval for the mean of five measurements is smaller than that for a single result.

> A 0.2121-g sample of an organic compound was burned in a stream of oxygen, and the CO2 produced was collected in a solution of barium hydroxide. Calculate the percentage of carbon in the sample if 0.6006 g of BaCO3 was formed.

> The ascorbic acid concentration in mmol/L of five different brands of orange juice was measured. Six replicate samples of each brand were analyzed. The following partial ANOVA table was obtained. a. Fill in the missing entries in the table. b. State the

> Sewage and industrial pollutants dumped into a body of water can reduce the dissolved oxygen concentration and adversely affect aquatic species. In one study, weekly readings are taken from the same location in a river over a two-month period. Some scien

> A prosecuting attorney in a criminal case presented as principal evidence small fragments of glass found embedded in the coat of the accused. The attorney claimed that the fragments were identical in composition to a rare Belgian stained glass window bro

> To test the quality of the work of a commercial laboratory, duplicate analyses of a purified benzoic acid (68.8% C, 4.953% H) sample were requested. It is assumed that the relative standard /reported results are 68.5% C and 4.882% H. At the 95% confidenc

> A standard method for the determination of glucose in serum is reported to have a standard deviation of 0.36 mg/dL. If s = 0.36 is a good estimate of σ, how many replicate determinations should be made in order for the mean for the analysis of a sample t

> A chemist obtained the following data for percent lindane in the triplicate analysis of an insecticide preparation: 7.23, 6.95, and 7.53. Calculate the 90% confidence interval for the mean of the three data, assuming that a. The only information about th

> A volumetric calcium analysis on triplicate samples of the blood serum of a patient believed to be suffering from a hyperparathyroid condition produced the following data: mmol Ca/L = 3.15, 3.25, 3.26. What is the 95% confidence interval for the mean of

> How many replicate measurements are necessary to decrease the 95% and 99% confidence limits for the analysis described in Problem 5-8 to ± 0.15 μg Cu/mL?

> How many replicate measurements are needed to decrease the 95% and 99% confidence limits for the analysis described in Problem 5-7 to ± 1.9 μg Fe/mL?

> Write expressions for the autoprotolysis of a. H2O. b. HCOOH. c. CH3NH2. d. NH3.

> An atomic absorption method for determination of copper in fuel samples yielded a pooled /reciprocating aircraft engine showed a copper content of 6.87 μg Cu/mL. Calculate the 95% and 99% confidence intervals for the result if it was based on a. A singl

> An atomic absorption method for the determination of the amount of iron present in used jet engine oil was found from pooling 30 triplicate analyses to have a standard deviation s = 2.9 µg Fe/mL. If s is a good estimate of σ, calculate the 95% and 99% co

> The last result in each set of data in Problem 5-4 may be an outlier. Apply the Q test (95% confidence level) to determine whether or not there is a statistical basis to reject the result.

> Calculate the 95% confidence interval for each set of data in Problem 5-4 if s is a good estimate of σ and has a value of set A, 0.015; set B, 0.30; set C, 0.070; set D, 0.20; set E, 0.0090; and set F, 0.15.

> Consider the following sets of replicate measurements: Calculate the mean and the standard deviation for each of these six data sets. Calculate the 95% confidence interval for each set of data. What does this interval mean?

> Discuss how the size of the confidence interval for the mean is influenced by the following (all the other factors are constant): a. The standard deviation σ. b. The sample size N. c. The confidence level.

> The accepted values for the sets of data in Problem 4-7 are set A, 9.0; set B, 55.33; set C, 0.630; set D, 5.4; set E, 20.58; and set F, 0.965. For the mean of each set, calculate a. The absolute error. b. The relative error in parts per thousand.

> Consider the following sets of replicate measurements For each set, calculate the (a) mean, (b) median, (c) spread or range, (d) standard deviation, and (e) coefficient of variation.

> From the normal curve of error, find the probability that a result is outside the limits of ±2σ from the mean. What is the probability that a result has a more negative deviation from the mean than -2σ?

> From the Gaussian (normal) error curve, what is the probability that a result from a population lies between 0 and +1σ of the mean? What is the probability of a result occurring that is between +1σ and +2σ of the mean?

> Why is 1g no longer exactly 1 mole of unified atomic mass units?

> Briefly describe or define and give an example of a. A strong electrolyte. b. A Brønsted-Lowry base. c. The conjugate acid of a Brønsted-Lowry base. d. Neutralization, in terms of the Brønsted-Lowry concept. e. An amphiprotic solute. f. A zwitterion

> Sally hires a maid to work in her home for $280 per month. The maid is 25 years old and not related to Sally. During 2019, the maid worked 9 months for Sally. a. What is the amount of Social Security tax Sally must pay as the maid’s employer? b. What is

> Stewart Beauf is a self-employed surfboard maker in 2019. His Schedule C net income is $126,503 for the year. He also has a part-time job and earns $16,100 in wages subject to FICA taxes. Calculate Stewart’s self-employment tax for 2019 using Schedule SE

> Dori is 58 years old and retired in 2019. She receives a pension of $25,000 a year and no other income. She wishes to put the maximum allowed into an IRA. How much can she contribute to her IRA?

> Bob is a single, 40-year-old doctor earning $190,000 a year and is not covered by a pension plan at work. What is the maximum deductible contribution into a Traditional IRA in 2019?

> Barry is a single, 40-year-old software engineer earning $190,000 a year and is not covered by a pension plan at work. How much can he put into a Roth IRA in 2019?

> What is the maximum amount a 55-year-old taxpayer and 52-year-old spouse can put into a Traditional or Roth IRA for 2019, assuming they earn $70,000 in total and are not participants in pension plans?

> What is the maximum amount a 45-year-old taxpayer and 45-year-old spouse can put into a Traditional or Roth IRA for 2019 (assuming they have sufficient earned income, but do not have an income limitation and are not covered by another pension plan)?

> Phil and Linda are 25-year-old newlyweds and file a joint tax return. Linda is covered by a retirement plan at work, but Phil is not. a. Assuming Phil’s wages were $27,000 and Linda’s wages were $18,500 for 2019 and they had no other income, what is the

> During the 2019 tax year, Irma incurred the following expenses Union dues = $244 Tax return preparation fee = 150 Brokerage fees for the purchase of stocks = 35 Uniform expenses not reimbursed by her employer = 315 If Irma’s adjusted gross income is $23,

> On January 3, 2019, Carey discovers his diamond bracelet has been stolen. The bracelet had a fair market value and adjusted basis of $7,500. Assuming Carey had no insurance coverage on the bracelet and his adjusted gross income for 2019 is $45,000, calcu

> Richard McCarthy (born 2/14/1965; Social Security number 100-10-9090) and Christine McCarthy (born 6/1/1967; Social Security number 101-21-3434) have a 19-year-old son (born 10/2/2000 Social Security number 555-55-1212), Jack who is a full-time student a

> In June of 2019, Maureen’s house is vandalized during a long-term power failure after a hurricane hit the city. The president of the United States declares Maureen’s city a disaster area as a result of the wide-scale vandalism. In which tax year may Maur

> Karen, 28 years old and a single taxpayer, has a salary of $33,000 and rental income of $33,000 for the 2019 calendar tax year. Karen is covered by a pension through her employer. a. What is the maximum amount that Karen may deduct for contributions to

> Jerry made the following contributions during 2019: His synagogue (by check) = $1,100 The Republican Party (by check) = 180 The American Red Cross (by check) = 200 His fraternal organization for tickets to a holiday party = 100 In addition, Jerry donate

> At the end of 2019, Mark owes $250,000 on the mortgage related to the 2016 purchase of his residence. When his daughter went to college in the fall of 2019, he borrowed $20,000 through a home equity loan on his house to help pay for her education. The in