IMG_6320

The protein concentration of a protein isolate was determined using the Bradford assay. Five dilution of bovine serum albumin (BSA) were prepared from a 5.00 mg/mL BSA stock solution. To these dilutions, 100 µl of Bradford reagent were added. After 5 minutes, the absorbance was taken at 595 nm. Standard # BSA, in mg/mL Volume of Bradford reagent, A595 in mL 1 5.0 0.000 1.00 5.0 0.134 3 2.00 5.0 0.265 4 3.00 5.0 0.388 4.00 5.0 0.497 The supernatant dilution was prepared by mixing 49 µL of the protein isolate with 16 µL water. The absorbance was taken 5 minutes after addition of 100 mL Bradford reagent. Calculate the protein concentration (in mg/mL) of the original isolate if the absorbance at 595 nm was 0.413. Note: Final answer format must be x.xxx (three decimal places). Round off only in the final answer. Do not round off in the middle of calculation.

An environmental chemist working for the Environmental Protection Agency (EPA) was directed to collect razor clams from a heavily-contaminated river superfund site and analyze them for their Ca+ content using graphite furnace atomic absorption spectrometry (GFAAS). The chemist dried the clams at 95 °C overnight and ground them in a scientific blender, resulting in approximately 50 g of homogenized dry weight. A representative 91.79 mg sample was taken from the approximately 50 g of dry material and dissolved in 100.0 ml. of 0.1 M HCI to create a sample solution. Using the method of standard additions, the chemist prepared five standard solutions in 100.0 ml volumetric flasks, cach containing 5.00 ml. aliquots of the sample solution. Varying amounts of a 85.0 ppb (ug/L) Cd+ standard were added to each of the flasks, which were then brought to volume with 0.1 M HCI. The Cd content of the solutions was then analyzed using GFAAS, resulting in the absorbance data given in the table. TTI…

Consider the following data: HX → X- + H+ Ką = 6.61 · 10- 5 H2A + НА + Н + Ka = 2.68 · 10-7 Calculate the Keg for the following reaction: H2A + X¯ + HA¯ +HX Record your answer in scientific notation to 3 sig figs.

Analytical chemist from Petroleum Development Oman extracted petroleum from crude oil and measured the quantity lost by the extraction to tell how much of the petroleum was. Quantity of Petroleum lost (%):10.8, 11.6, 9.4, 7.8, 9.2, 9.5, 10.6, 11.6Should the value 7.8 be rejected from the set of the above results.

(10) You have 4 powdered samples, A, B, C, & D. One sample contains fullerenes, C16 to C70. Another is nano diamond. Another one is a mixture of C60 and carbon nanotubes. The 4th is a mixture of graphite & graphene. Indicate the analytical methods you would use to identify and distinguish the samples from each other.

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?

A chemist working in a hospital clinical laboratory obtained the following values for uric acid in blood serum: 4.63, 4.58, 4.82, 4.31, 4.67 and 4.60 mg%. What value should be reported as the mean? Value of QT at 90 % confidence level is 0.56.

7) The homogeneity of the chloride level in a water sample from a lake was tested by an analyst. Below are the concentration in parts per million (ppm) of Cl: 27.32, 27.22, 27.21, 27.24, 27.20 i. Determine the mean and median. ii. Calculate the confidence limit at 90%. iii. Identify a possible outlier and use the Q-test to determine whether it can be retained or rejected at 90% confidence level

A group of students titrate a calcium carbonate standard solution repeatedly in five experimental trials. Based on the five trials, the group determines that the average concentration of the standard is 80.5 ppm with a standard deviation of 0.5 ppm. Using the equation for the Student's t confidence interval found in Appendix 1 of your lab manual and the t-value for a 95% confidence interval, calculate the confidence interval for which there is a 95% chance of finding the "true value" of the standard solution's concentration based on the data. Put your answer in the format # lower limit < "true value" < # upper limit. (Appendix 2 has an example that may be helpful.)

The percentage of an additive in gasoline was measured six times with the following results: 0.13; 0.12; 0.16; 0.17; 0.20 and 0.11%. What is the 99% confidence interval for the additive percentage?

Today the only form of liquid acetaminophen on the market has a concentration of 160 mg acetaminophen per 5.0 mL. How would you instruct parents of an infant to give a total of 40 mg of acetaminophen to their infant?  Your directions should be clear, not lead to the confusion caused by the physician in the case study, and include the volume of liquid acetaminophen they should give their son.  Please show how you calculated the volume needed to provide 40 mg of acetaminophen.

A new method for glucose determination in serum (Method A) is to be compared to the established method (Method B). The table below shows the measured glucose concentration by each method for each patient. Is there a difference in the two methods at the 95% confidence interval? Patient1 Patient2 Patient3 Patient4 MethodA(mg/L) 1044 MethodB(mg/L) 1028 720 711 845 820 800 795 Patient5 957 935

1 A volumetric iron analysis on triplicate samples of the blood serum of a patient believed to be suffering from anaemia condition produced the following data: 3.15, 3.25, 3.26 mmol Fe/L. What is the 95% confidence interval for the mean data, assuming: a) No prior information about the precision of the analysis? b) S>0 = 0.056 mmol Fe/L?

Concentration (mg/ml) Time (min) 8.5 0.5 6.8 5.4 1.5 4.0 2 3.2 2.5 2.5 3 What will be the slope of the line using the given first and second values? What will be the y-intercept, still using the given first and second values? Completely state the equation of the line. nlcot olN5

A new procedure for the rapid determination of sulphur in kerosene was tested on a sample known from its method of preparation to contain 0.123% S (µ = 0.123% S). The results for % S were 0.112, 0.118, 0.115, and 0.119. Determine whether the data indicate that there is a bias in the method at the 95% confidence level

(9.29 × 105/8)-20.81 =  with correct sig figs

25ml of water is used to extract NO ‐1 from A wet soil sample weighing 10 grams. Another sample of 10-gram soil sample is oven dried and found to weigh 5 grams when dry. The [NO ‐1] of the extract is determined to 5mg NO ‐1/ml. What is the NO ‐1 of the soil in the unit's mg of NO ‐1 /g dry soil?

Dr. Caras was characterizing a cytochrome (an iron containing protein) from a new strain of bacteria. He obtained eight measurements of the percent iron in the protein: 0.5806%, 0.5804%, 0.5796%, 0.5794%, 0.5919%, 0.5795%, 0.5805%, and 0.5793%. Calculate the mean (x) and standard deviation (s) for these results. x = 0.5812 2.84 X10-3 Incorrect Use the Grubbs test to determine if of these values is an outlier. What is the value of Gcalculated? Gcalculated 0.494 Incorrect Should this potential outlier be rejected with 95% confidence? Critical values of G can be found in this table. O The potential outlier should be rejected. The potential outlier should be kept. % % ро en uti si luti

Construct the expression for Kc for the following reaction. 1 3NO(g) = N20(g) + NO2(g) Construct the expression for Kc for the following reaction. 2 X 4HCI(aq) + O2(g) = 2H20(1) + 2C12(g) > Construct the expression for Kc for the following reaction. 3 CH4(g) + 2H2S(g) = CS2(g) + 4H2(g) Construct the expression for Kc for the following reaction. 4 X 2Cu*(aq) + Zn(s) = 2Cu(s) + Zn²*(aq) >

Two different laboratories within a company further studied the morantel recovery percentage in shrimp when spiking with 10 ug/kg. The results from both labs are presented below. Shrimp Sample Laboratory 1 (ug/kg) Laboratory 2 (ug/kg) 108.82 113.36 2 101.59 107.47 3 102.17 109.01 a. A 4th shrimp sample was analyzed for morantel recovery percentage using laboratory 1. The result was 99.4%, can any of the data be thrown out using the Q and/or Tn test using the 95th percentile? b. Is there a statistical difference (90th percentile) between the two laboratories results in the study?

Appendix A – Commercially available analgesics. - No: Commercial Aspirin Caffeine Acetaminophen Ibuprofen name Bayer Aspirin Generic Aspirin 1 2 3 Excedrin X 4 Anacin No-doz Tylenol 6 7 Motrin Table 1: Complete this table Distance travelled Known Rf Value (ст) Solvent 5.2 Aspirin 3.0 Acetaminophen 1.8 Caffeine 0.40 Ibuprofen 3.5 Calculate Rf value for all above compounds. Write formula and show all calculations.

Dr. Caras was characterizing a cytochrome (an iron containing protein) from a new strain of bacteria. He obtained eight measurements of the percent iron in the protein: 0.4908%, 0.4902%, 0.4899%, 0.4899%, 0.5012%, 0.4891%, 0.4903%, and 0.4892%. Calculate the mean (x) and standard deviation (s) for these results. x = S= Use the Grubbs test to determine if one of these values is an outlier. What is the value of Gcalculated? Gcalculated = % %

Replicate measurements performed on the moisture content of a flour sample produced the following values (mg/g): 13.76, 13.99, 13.94, 13.97, 13.95, 13.96, 14.17, 13.86. At 95% confidence level, this was the lower .confidence limit for these measurements: O 13.85 13.95 14.05 ONone of the above

1) Listen -5 The Ksp value for calcium sulfate [CaSO4] is 2.40 X 10 and a professor made 1825 mL of a CaSO4(ag) solution but then one of his graduate student accidentally poured in a 0.125 M solution of calcium phosphate [Cag(PO4)2] solution. You may ignore the additional volume coming from the Ca3(PO4)2 solution to make the calculation simpler. Calculate the new sulfate (SO42) ion concentration at equilibrium with this common ion effect. 6.40 x 10-5 5.25 x 10-5 6.21 x 10-5 5.44 x 10-5 201591..docx LAB EXP. #3 -..docx Show All

Eight replicate measurements were made on a test solution producing the following results for the concentration of sodium ion (mg/L): 63.91, 65.92, 69.98, 64.24, 65.45, 65.82, 66.51, 65.11. The value 69.98 is an outlier suspect. A Q-test at 95% confidence level will lead to this conclusion with respect to the suspect value: O Should be thrown away Should not be thrown away There is not enough data to draw a conclusion None of the above

Opioid dependence is described in the Australian Medicines Handbook as a chronic, frequently relapsing illness. One approach to managing opioid dependence is opioid substitution therapy (opioid maintenance therapy). The figure below depicts concentration-response curves for two drugs used in the management of opioid dependence compared to heroin: 100 LEGEND 60 U 20 0 0.0001 0.001 0.01 0.1 1 10 [Drug] (Log Units) Question: From the drugs listed below, select the options that are most likely to be represented by the concentration-response curves for: Drug A: Drug B: Buprenorphine Naloxone Methadone Naltrexone % Maximal Response 100 Heroin Drug A Drug B

(a) Is it true that 26.3 mpg gasoline translates to 319 g CO:/mi? i. Convert mpg (miles per gallon) to miles per kg (of gasoline) using the density of gasoline ii. Convert kg of gasoline to kg of C assuming the overall formula for gasoline is CıH1a5 ii. Convert kg of C to kg of CO2 iv. Now finally compute g CO:/mi corresponding to 26.3 mpg and compare to 319 g CO2/mi

Given: Trial 1 25.00 0.00 10.40 10.40 Trial 2 25.0 10.40 20.13 9.73 Volume of Ca(OH)2 (mL) Initial burette reading (mL) Final burette reading (mL) Volume of HCl used in titration (mL) answer in 3 significant figures. Trial 3 25.0 20.13 30.29 (a) write the neutralization reaction involved in the experiment. (b) Calculate the molarity of Ca2+ (M). Show the complete solution. 10.16

(60 pts) In the following reaction between p-Acetaminophenol (C6H7NO)(s) and Acetic Anhydride      (C4H6O3)(aq)Acetaminophen (C8H9NO2)(s) and Acetic Acid CH3COOH(aq) were formed. 0.157g of  p-Acetaminophenol reacted with 0.48g of Acetic Anhydride and 0.198g of Acetaminophen was produced.  SHOW WORK!  C6H7NO(s)         +          C4H6O3(aq)        →       C8H9NO2 (s)          +         CH3COOH(aq)    Calculate the moles of  p-Acetaminophenol reacting.       Calculate the moles of Acetic Anhydride reacting.       Calculate the moles of Acetaminophen produced.       What was the limiting reagent?     Calculate the Theoretical Yield of Acetaminophen.       Calculate the Percent Yield of Acetaminophen.       Your Product (Aspirin) Produced.

1. Certified Reference Material (CRM), GSS-5, is certified to contain 40.67 ± 3.33 mg/kg of Ni in soil. An analysis of the CRM gives values of 40.39, 41.98, 43.64, 44.38, and 45.96 mg/kg. Determine the tcalc. value and determine if your results differ from the expected results at the 90 % confidence level?

7.+ 8.

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 227.5What is the 95% confidence interval for the mean?

The molarity of a solution is determined by four separate titrations or replicates, where the obtained data was 0.4120, 0.4920, 0.3920, and 0.4320 M. Calculate the standard error of the mean for the above data. O 0.00185 O 0.02160 O 0.43200 O 0.04320 O 0.01080