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Document lab experiments in a standard format in a laboratory notebook
Assessment Strategies
In lab assignments
Criteria
The notebook contains an accurate and complete index
The notebook includes an experimental objective, introduction with relevant theory and reaction schemes, chemical safety and disposal information, an accurate table of reference data, procedural details, and all necessary data tables prior to the beginning of each experiment
Each completed experiment is accurately documented
Each experiment's report is complete
All sections of each report are substantive and accurate
Each report includes a concise discussion indicating whether or not the experimental objective was met based on experimental results
The information given in the notebook is sufficient to allow another individual with comparable skill and experience to replicate the experiment
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Identify structures of unknown chemicals using infrared (IR) spectroscopy
Assessment Strategies
In lab reports
In pre-laboratory assessments
By demonstrated lab performance
On a written test/lab practical exam
Criteria
IR spectra include a complete, accurate and specific title
IR spectra include peaks labeled with relevant molecular vibrations
IR spectra include the proposed structure consistent with the spectrum
IR spectra are accompanied by a database match, along with percent similarity comparing the experimental spectra to reference spectra
Matching peaks found in both the experimental and database spectra are highlighted
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Identify structures of solids using melting point analysis
Assessment Strategies
On a written test/lab practical exam
By demonstrated lab performance
In pre-laboratory assessments
In lab reports
Criteria
The literature value for melting point of the pure substance is documented
The melting range is correctly measured using a melting point apparatus
The average melting range and melting “point” are correctly calculated based on experimental data
The percent deviation between the experimental and literature melting points is correctly calculated based on experimental data
A concise comparison of the experimental and reference melting point is included in the laboratory report
The relative purity of the substance is assessed based on the width of the melting range and the percent deviation in the melting point
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Separate components from a liquid mixture using distillation techniques
Assessment Strategies
In lab reports
In pre-laboratory assessments
By demonstrated lab performance
On a written test/lab practical exam
Criteria
A simple distillation apparatus is correctly assembled
A fractional distillation apparatus is correctly assembled
A binary mixture is successfully separated using simple distillation
A binary mixture is successfully separated using fractional distillation
Characterization techniques, such as thin layer chromatography, refractometry, infrared spectroscopy, and/or gas chromatography are utilized to confirm identity and purity of isolated components from the mixture
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Separate components of a solid mixture using thin layer chromatography (TLC)
Assessment Strategies
In lab reports
In pre-laboratory assessments
By demonstrated lab performance
On a written test/lab practical exam
Criteria
The components of a thin layer chromatography experiment, including the stationary phase, mobile phase, etc., are identified
The retardation factor (Rf) of substances is accurately measured
The percent deviation in the retardation factor is accurately calculated
The components of a mixture are identified using standards
The purity of a sample is assessed using the results of TLC analysis
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Identify an unknown chemical using refractometry
Assessment Strategies
In lab reports
In pre-laboratory assessments
By demonstrated lab performance
On a written test/lab practical exam
Criteria
The refractive index of substances is accurately determined using a refractometer
The experimentally measured refractive index is corrected to allow comparison to a reference refractive index
The percent deviation in the refractive index is accurately calculated
The corrected refractive index is used to confirm the identity of an unknown substance
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Identify components of a mixture using gas chromatography (GC)
Assessment Strategies
In lab reports
In pre-laboratory assessments
By demonstrated lab performance
On a written test/lab practical exam
Criteria
Samples are prepared for injection into the gas chromatograph
Samples are effectively analyzed using a gas chromatograph
Accurate retention times are measured for each component of a mixture
Accurate retention times are measured for standards of each potential component of a mixture
The percent deviation in the retention time is accurately calculated
The identity of each component in a mixture is accurately identified
The purity of a sample is assessed based on the experimental chromatogram
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Purify a sample using recrystallization
Assessment Strategies
In lab reports
In pre-laboratory assessments
By demonstrated lab performance
On a written test/lab practical exam
Criteria
Determine appropriate recrystallization solvent(s) for a given sample
Perform a recrystallization of a solid sample
Recover the purified solid using vacuum filtration
Perform appropriate analyses on the recrystallized solid to assess its purity
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Evaluate the purity of a final purified sample chemical
Assessment Strategies
In lab reports
In pre-laboratory assessments
By demonstrated lab performance
On a written test/lab practical exam
Criteria
Appropriate method(s) of analysis are chosen for a given sample
A qualitative analysis of the purity of a sample is presented based upon the results of each method of analysis
A quantitative analysis of the purity of a sample is presented based upon the results of each method of analysis
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Present experimental results in the format of a Journal of Organic Chemistry communication
Assessment Strategies
In a written paper
Criteria
Paper has a succinct and descriptive title
Abstract details experimental objective, techniques and analyses used, and highlights key experimental findings
Introduction provides relevant background materials necessary to understand relevant theory for interpreting experimental findings
Data is presented in numbered data tables, which include a descriptive title
All figures include a figure number, descriptive title, and a succinct description
Discussion section carefully analyzes experimental findings, using data and calculations as appropriate
Conclusion statement includes key results
Conclusion statement indicates whether or not the experimental objective was met
In-text citations are used as appropriate
References are included, following referencing guidelines outlined in "The ACS Style Guide"
Experimental details in appendix are presented in a manner consistent with a Journal of Organic Chemistry communication
Relevant calculations are presented in the appendix