An analysis of city drinking water for total hardness was done by two students in the laboratory and produced the following results (in ppm CaCO3): Student A: 228.3, 226.4, 226.9, 227.1, and 228.6. Student B: 229.5, 226.1, 230.7, 223.8, and 227.5 What is the 95% confidence interval for the mean?

An analysis of city drinking water for total hardness was done by two students in the laboratory and produced the following results (in ppm CaCO3): Student A: 228.3, 226.4, 226.9, 227.1, and 228.6. Student B: 229.5, 226.1, 230.7, 223.8, and 227.5 What is the 95% confidence interval for the mean?

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter5: Errors In Chemical Analyses

Section: Chapter Questions

Problem 5.12QAP

See similar textbooks

Related questions

Q: . Find the molarity of the HNO3 solution and its absolute uncertainty.

A: As per the balanced chemical reaction, 2 mol of HNO3 reacts with 1 mol Na2CO3. Now, No of moles =…

Q: The Ksp value for calcium sulfate [CaSO4] is 2.40 X 10-5 so if a professor made 1825 mL of a…

A: In this question, we want to determine the mass of the SO42- ion in grams unit. You can see details…

Q: 1. What's the slope of the calibration curve? 3.95 x 10-5 4.17x10-5 1 20484 25257 2. What's the…

A: The linear regression equation of the calibration curve is: Y = 25257X - 114.32

Q: A titrimetric method for the determination of calcium in limestone was tested with the analysis of a…

Q: Plot the following data and perform linear regression to obtain the value of the slope, the value of…

A: The Plot is drawn in the Microsoft office Excel and it is follows.

Q: (3) In a titration, the % analyte is computed from the following equation: Vol (titrant) x M…

Q: The concentration of chloride in seawater can be determined by a flow injection analysis. The…

A: To find concentration of Cl- in the sample at an absorbance of 0.443.

Q: Find the median of the following data: 160, 180, 200, 280, 300, 320, 400 а. 200 b. 240 С. 280

Q: The Ksp value for calcium sulfate [CaSO4] is 2.40 X 10-5 so if a professor made 1825 mL of a…

A: Ksp = [Ca2+][SO42-] if solubility is s mol/L then: Ksp = s2 Number of mol = Molarity x Volume in L…

Q: Find the median of the following data: 160, 180, 200, 280, 300, 320, 400 a. 280 b. 200 С. 240

Q: For the calculation of sd, shouldn't it be (0.97-1.09) and so on... because 0.97 = x and 1.09 =…

A: The general equation to find the standard deviation is: ∑i=2n(Xi-μ)2NwhereXi = Experimental valuesμ…

Q: A second spectrophotometric method for the quantitative analysis of Pb2+ in blood yields an Ssamp of…

A: The value of sensitivity of the method for the analyte (kA) is calculated using sample signal…

Q: You are trying to come up with a drug to inhibit the activity of an enzyme thought to have a role…

A: For a competitive inhibitor, the apparent Km of the enzyme is given as:

Q: A method for the detection of morphine is used to generate a calibration curve in which the assay…

A: The explanation is given below-

Q: (Concentration) You are tasked to prepare 300.000 ppb of a sodium carbonate standard for a…

A: Parts per billion (ppb) concentration is defined as: mass of solute (in grams)volume of solution (in…

Q: A 0.1 M solution of acid was used to titrate 10 ml of 0.1 M solution of alkali and the following…

A: Given data :- 0.1 M solution of acid was used to titrate 10 ml of 0.1 M solution of alkali Volumes…

Q: Given the following data, calculate the 95% confidence interval. 0.452 0.453 0.448 0.456…

A: Given , Average = 0.4534 Standard deviation = 0.003847

Q: prepare a solution with a concentration of 0.500 mol·dm⁻³ in a 250 cm³ volumetric flask. [Round the…

A: Concentration (M) = 0.500 M/dm3 Volume = 250 cm3 =250/1000 = 0.250 dm3 Now, we know, Molarity(M)…

Q: The following data represented the concentration of ofloxacin present in chicken meat samples: 4.17,…

A: Percentage relative standard deviation is given by formula % relative SD =(standard deviation /…

Q: The gravimetric factor used to express CoCBr6·H20 in a sample that is finally weighed as PbClBr is…

A: Gravimetric factor

Q: The concentration of chloride in seawater can be determined by a flow injection analysis. The…

A: We are given Cl- concentration and absorbance data for calibration standards. We have to find Cl-…

Q: A titration was carried out to determine the volume of base needed to neutralize an acid. Five runs…

A: The neutralization reaction or the acid-base reaction is often employed as the basis for determining…

Q: 44.8 R Benzoin Tincture Peru Balsam Cold Cream Sig: cold sore ointment 18 ml 10 g 70 g If benzoin…

Q: (25.3-9) Find a 99% confidence interval for the mean of the copper content of a brass alloy sampled…

Q: The analysis shows different concentrations based on replicate determinations of Zn in a water…

A: Absolute error is the difference between the measured value and actual value. Its modulus i.e.…

Q: -). A new procedure for determining cholesterol in blood serum was used with a NIST standard sample…

Q: fat sample with combination of acids contain standard hydrochloric acid for blank and sample with…

A: Saponification : The process in which fats, oils, or lipids are converted into saop and alcohol by…

Q: The peak integrations of a chromatogram resulting from a GC analysis of a mixture containing…

A: Area under the curve of GC is correspond to mass of that component.

Q: Standardization of Sodium Thiosulfate Solution Primary Standard used: Potassium Dichromate…

A: The formula of potassium dichromate is K2Cr2O7

Q: ± 0.00098 18 Bromocresol green 0.08641 ± 0.00113 29 Is the difference between indicators

A: 95 % confidence interval for a population mean can be represented as

Q: 1. What is the MW of the analyte? 2. What is the meq of the analyte? 3. What is the weight (in…

A: Since you have asked a question with multiple subparts we will answer the first three for you. To…

Q: According to the information given below, compute the correlation coefficient and the covariance…

A: Given Standard deviation of the portfolio (stock A and stock B) : 0.37 Standard deviation of the…

Q: replicate determination of the lead content of a blood sample (0.752, 0.756, 0.752, 0.751 and 0.760…

Q: A wet pipette was used to transfer 10.00 mL of 1M HNO3 in the determination of ΔHrxn. [magnitude of…

A: Since you have posted multiple questions, we are entitled to answer the first only.

Q: ▪ A pharmaceutical analyst needs to do quality control of a sodium furosemide solution. The max for…

A: Absorbance = Absorptivity coefficient × Concentration × Path length Path length = 1 cm Absorptivity…

Q: If the volume used to make 100 mL of std 1 is 2 uL what is the concentration in M used to make std…

A: Concentration of std 1 is 16 ppm.

Q: Chemistry The levels of an organic pollutant (P) in the groundwater at the perimeter of a plant…

A: A question based on tools in analytical chemistry that is to be accomplished.

Q: Analysis was run on samples from a known CRM with 8.85% Fe. The following results for %Fe were…

A: 1)The null and alternate hypothesis are: H0= (the analysis is accurate ) H1= (the analysis is not…

Q: Q1: The table below shows the Oxygen purity and Hydrocarbon levels observed in five tests performed…

Q: potassium hydrogen phthalate is a primary standard used to measure the concentration of NaOH…

A: Due to the buoyancy force by air, the mass of an object measured in the air is always appear to be…

Q: The morphine levels (%) of seven batches of seized heroin were determined with the following…

A: Given: True value = 20% Confidence level = 95 % Results (%) : 15.1, 21.2, 18.5, 25.3, 19.2, 16.0,…

Q: 1. What the difference between primary and secondary standard substances?

A: Since we only answer one question at a time, so we'll answer the first one. Please resubmit the…

Q: Analysis was run on samples from a known CRM with 8.85% Fe. The following results for %Fe were…

A: 1)The null and alterate hypothesis are: H0= (the analysis is accurate ) H1= (the analysis is not…

Q: Table 1-4: Spectrophotometric readings of a dye dilution series m of Dye A620 Reading of Sample A…

A: We are given absorbance reading for sample-A and sample-B for different mass values of the dye. We…

Q: A. Standardization of NaOH solution with KHP Trial 1 Trial 2 Weight of KHC,H,o. 1.596 g 1.819 g…

Q: Plot Density(g/mL) vs Mass (g) 20 18 y = 10.01x -0.017 R² = 1 16 14 12 10 6 0.2 0.4 0.6 0.8 1 1.2…

Q: What weight of mercury bichloride should be taken as sample, assuming 100% purity, so that 0.5 g og…

A: Weight is calculated as, (weight of sample * GF)/ Weight of analyte.

Q: A chemist working in a hospital clinical laboratory obtained the following values for uric acid in…

A: The given values are 4.63, 4.58, 4.82, 4.31, 4.67 and 4.60 mg To find: Mean value

Q: Certified Reference Material (CRM), GSS-5, is certified to contain 40.67 ± 3.33 mg/kg of Ni in soil.…

Q: 10) The following results were obtained in an analysis of iron content in an ore sample. The results…

Question

An analysis of city drinking water for total hardness was done by two students in the laboratory and produced the following results (in ppm CaCO₃):

Student A: 228.3, 226.4, 226.9, 227.1, and 228.6.

Student B: 229.5, 226.1, 230.7, 223.8, and 227.5

What is the 95% confidence interval for the mean?

Expert Solution

This question has been solved!

Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.

This is a popular solution!

SEE SOLUTION Check out a sample Q&A here

Step 1

VIEW

Step 2

VIEW

Step 3

VIEW

Trending now

This is a popular solution!

Step by step

Solved in 3 steps

SEE SOLUTION Check out a sample Q&A here

Knowledge Booster

Learn more about

Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.

Similar questions

For the calculation of sd, shouldn't it be (0.97-1.09) and so on... because 0.97 = x and 1.09 = mean? and the formula for sd is squared of the summation of (x-mean)^2 divide by n?
1. Replicate analyses of the lead content in a blood sample gave the following results: 0.789, 0.781, 0.795, 0.792, and 0.784 ppm Pb. Calculate the mean, standard deviation, variance, relative standard deviation, and standard deviation of the mean of the data.
A volumetric calcium analysis on samples of the blood serum of a patient believed to be suffering from a hyperparathyroid condition produced the following data: mmol Ca/L = 3.10, 3.08, 3.28, 3.15, 3.26, 3.12, 3.14, 3.18, 3.25, 3.11, 2.95. Calculate: Mean Standard deviation Coefficient of variation What is the 95% confidence interval for the mean of the data, assuming no prior information about the precision of the analysis? Apply the Q test to the following data sets to determine whether the outlying result should be retained or rejected at the 95% confidence level. ( work on the first measurements according to your case)
Chemistry The levels of an organic pollutant (P) in the groundwater at the perimeter of a plant were a cause for concern. A 10 mL sample of the water was taken and the pollutant was extracted with 95% efficiency using 25 mL of diethyl ether. GC was used to analyse the concentration of P in diethyl ether. A calibration curve was plotted for a series of standards of P which yielded the following results: Peak Area Toluene Conc. (µg/ml) 12,000 2.6 23,700 5.0 35,500 7.7 46,800 9.9 31,250 Sample Determine the concentration of P in ppb in the initial groundwater sample.
A second spectrophotometric method for the quantitative analysis of Pb2+ in blood yields an Ssamp of 0.712 for a 5.00 mL sample of blood. After spiking the blood sample with 5.00 μL of a 1560 ppb Pb2+ external standard, an Sspike of 1.546 is measured. What is the concentration of Pb2+ in the original sample of blood?
A quantitative analysis for an analyte gives a mean concentration of 12.6 ppm. The standard deviation due to the method, sm, is found to be 1.1 ppm, and that due to sampling, ss, is 2.1 ppm. By how much does the overall variance change if sm is improved by 10% and ss is improved by 15%?
To determine the organic material in a dried lake bed, the percent carbon by mass is measured at two different locations. To compare the means of the two different locations, it must first be determined whether the standard deviations of the two locations are different. For each location, calculate the standard deviation and report it with two significant figures. What is the calculated F value for comparing the standard deviations? Are the standard deviations for the two locations significantly different at the 95% confidence level? ample Location 1 (% C) Location 2 (% C) 1 10.40 10.10 2 10.30 10.90 3 10.30 10.20 4 10.40 10.70 5 10.30 10.30
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 the data, assuming no prior information about the precision of the analysis?
You are trying to come up with a drug to inhibit the activity of an enzyme thought to have a role in liver disease. In the laboratory the enzyme was shown to have a Km of 1.0 x 10-6 M and Vmax of 0.1 micromoles/min.mg measured at room temperature. You developed a competitive inhibitor. In the presence of 5.0 x 10-5 M inhibitor, the apparent Km of the enzyme was found to be 1.5 x 10-5 M. What is the Ki of the inhibitor?
StatisticalAnalysis of Data. Provide what isasked. a.Mean values of ppm Ca and ppm Mg .b.Median values of ppm Ca and ppm Mg. c.Std. dev. of ppm Ca and ppm Mg.
If an instrument gives a response of 1240 for a standard containing 8 ppm of a substance, how much if this substance is in a sample that gives a response of 1705? Are any assumptions needed?
Qq.1. Subject :- Account