CHMB16H3 Lecture Notes - Strong Electrolyte, Molar Concentration, Volumetric Flask

64 views5 pages

jadedolphin901

14 Oct 2012

School

Department

Course

Professor

For unlimited access to Class Notes, a Class+ subscription is required.

Document Summary

History: glp is a formal regulation that was created by the fda in 1978, used world-wide now, started in the u. s. a, in 1981, oecd (organization for economic co-operation and development ) produced glp principles that are international standard. Objectives of glp: glp makes sure that the data submitted are a true reflection of the results that are obtained during the study, makes sure data is traceable, promotes international acceptance of tests. Mission of glp: test systems, archiving of records and materials, apparatus, material and reagent facilities, qa programs, performance of the study, reporting study results, standard operating procedures (sop, personnel and test facility organization. 1: definition of raw data, keeping records, reporting, storage, mixing and retrieval of data. Statistical procedures for data evaluation: practitioners in a particular field may adopt certain standards which are deemed acceptable within their field statistical procedures are not just chosen from a textbook, regulatory agencies often describe acceptable statistical procedures.

Related Questions

Internal Standards

Some analytical methods are subject to one or more common sources of variability in the instrument response. One method aimed at overcoming this variability is the internal standard method. In this method, a known amount of a compound similar to the analyte is added to each standard and sample. Since we know the concentration of the internal standard (IS), we can use the IS response as an indicator of variability. In this type of calibration curve, the quantity plotted on the y-axis is not simply the instrument signal for the analyte, but rather the ratio of the analyte signal to the IS signal.

The IS method is commonly used in gas chromatography, because of the variability inherent in the small volumes injected into the instrument. In the forensic lab, blood alcohol measurements are one of the most common analyses performed. This dry lab example will use blood alcohol data.

You will use ethanol standards that you have purchased. You have 5 of these, with concentrations of 0.050, 0.080, 0.100, 0.200, and 0.300 %w/v of ethanol. You also have a blank, which doesnât contain any ethanol.

You will use n-propanol as the internal standard. You have made up a 0.0300% (v/v) solution of propanol.

You have one sample to run.

You add 2 mL of each of the standards and the sample to GC vials. Then you add 0.450 mL of the internal standard n-propanol to each vial. You get the data below.

Ethanol concentration, % (w/v)	Peak area for ethanol (pA*sec)	Peak area for n-propanol pA*sec)	Ratio of ethanol area to propanol area

First, make a calibration curve using only the area of the ethanol peak and the concentrations of the standards. As in Part 1 a and b, prepare and print a calibration curve including the linear least squares equation of the line equation and the R² value, and print a copy for your report. Also, calculate the concentration of your sample and the uncertainty (95% confidence interval), as well as the uncertainty of the unknown determination on a percentage basis, and include these values in your report. .

Next, make a calibration curve based on the ratio of ethanol area to propanol area and the concentrations of the standards. As in the previous question, prepare and print a calibration curve including the linear least squares equation of the line equation and the R² value, and print a copy for your report. Also, calculate the concentration of your sample and the uncertainty (95% confidence interval), as well as the uncertainty of the unknown determination on a percentage basis, and include these values in your report. .

At a blood alcohol concentration of 0.08% (w/v) or more a person is considered impaired. Briefly discuss whether the calculated results for the sample in e and f above support criminal charges of impairment.

Report Requirements:

Spreadsheet with graphs and calculations. Prepare separate sheets in one excel file for each of the following:

Data Set 1

Data Set 2

Calibration with external standard

Standard addition with one standard (optional, could submit hand or type written calculation only)

Standard addition with multiple additions

Internal standard peak areas

Internal standard peak area ratios

Print-outs of graphs

Data Set 1

Data Set 2

Calibration with external standard

Standard addition with multiple additions

Internal standard peak areas

Internal standard peak area ratios

Results

Fill in the table below with results from the spreadsheet. Remember to include units.


	Concentration of unknown	Uncertainty of unknown	Uncertainty of unknown in terms of %

	Concentration of unknown	Uncertainty of unknown	Uncertainty of unknown in terms of %

2d	Concentration of unknown	Uncertainty of unknown	Uncertainty of unknown in terms of %

	Concentration of unknown	Uncertainty of unknown	Uncertainty of unknown in terms of %

	Concentration of unknown	Uncertainty of unknown	Uncertainty of unknown in terms of %

Short answers/additional tables

Section 1c:

Section 1d:

Section 1e2:

Section 2a Table:

Section 3b Table:

Section 3b4 calculation

Section 3b5

Section 4d Table with calculated ratios

Section 4g

Answer Questions 1-4 please

CHMB16H3 Lecture Notes - Strong Electrolyte, Molar Concentration, Volumetric Flask

Document Summary

Get access

Related Documents

ACC 621 Chapter Notes - Chapter 1-15: Financial Audit, External Auditor, Internal Audit

Related Questions