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- https://chem.libretexts.org/Courses/SUNY_Oneonta/Chem_221%3A_Organic_Chemistry_I_(Bennett)/2%3ALab_Textbook_(Nichols)/03%3A_Crystallization/3.04%3A_Crystallization_Theory/3.4B%3A_Cooling_SlowlyThe difference in crystal lattice energy between pure and impure solids is marginal, so a solution must be cooled SLOWLY to allow for differentiation. If a hot solution is plunged immediately into an ...The difference in crystal lattice energy between pure and impure solids is marginal, so a solution must be cooled SLOWLY to allow for differentiation. If a hot solution is plunged immediately into an ice bath, the system will favor the formation of a solid (any solid!) so strongly that there may be little preference for purity. Impurities can become engulfed in the developing solid and trapped as solutes are deposited unselectively onto the growing solid.
- https://chem.libretexts.org/Courses/SUNY_Oneonta/Chem_221%3A_Organic_Chemistry_I_(Bennett)/2%3ALab_Textbook_(Nichols)/05%3A_Distillation/5.05%3A_Steam_Distillation/5.5B%3A_Uses_of_Steam_DistillationThe most common use of steam distillation is the extraction of natural products from plant materials. This is the main industrial method for obtaining plant essential oils, used in fragrances and pers...The most common use of steam distillation is the extraction of natural products from plant materials. This is the main industrial method for obtaining plant essential oils, used in fragrances and personal hygiene products. As so many products can be isolated in this way, this technique is regularly performed in teaching labs.
- https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Organic_Chemistry_Lab_Techniques_(Nichols)In this resource you will find theory and procedures on the main organic lab techniques (chromatography, crystallization, extraction, distillation) as well as general concepts on how to set up and hea...In this resource you will find theory and procedures on the main organic lab techniques (chromatography, crystallization, extraction, distillation) as well as general concepts on how to set up and heat apparatuses (see the Table of Contents tab for a more complete listing of topics). All procedures are accompanied by step-by-step pictures, and graphics are heavily utilized throughout the resource.
- https://chem.libretexts.org/Courses/Martin_Luther_College/Organic_Chemistry_-_MLC/02%3A_Tools_of_Organic_Chemistry/2.02%3A_Column_Chromatography/2.2.04%3A_Crystallization/2.2.4.02%3A_Uses_of_Crystallization/2.2.4.2B%3A_Purification_of_Product_MixturesIf the crude product of a chemical reaction is a solid, it may be crystallized in order to remove impurities.
- https://chem.libretexts.org/Courses/SUNY_Oneonta/Chem_221%3A_Organic_Chemistry_I_(Bennett)/2%3ALab_Textbook_(Nichols)/06%3A_Miscellaneous_Techniques/6.04%3A_Chemical_Tests/6.4B%3A_FlowchartsIn some teaching labs, a combination of spectroscopy and chemical tests are used in determination of an unknown. If available, an infrared spectrometer is very useful in determining possible functiona...In some teaching labs, a combination of spectroscopy and chemical tests are used in determination of an unknown. If available, an infrared spectrometer is very useful in determining possible functional groups present in an unknown. The following flowcharts summarize key signals present in an IR spectrum, and chemical tests that can be used to support or narrow down structural identification.
- https://chem.libretexts.org/Courses/SUNY_Oneonta/Chem_221%3A_Organic_Chemistry_I_(Bennett)/2%3ALab_Textbook_(Nichols)/03%3A_Crystallization/3.05%3A_Procedural_Generalities/3.5C%3A_CharcoalActivated charcoal is sometimes used to remove small amounts of colored impurities from solution. Activated charcoal has a high affinity for conjugated compounds, whose flat structures wedge themselve...Activated charcoal is sometimes used to remove small amounts of colored impurities from solution. Activated charcoal has a high affinity for conjugated compounds, whose flat structures wedge themselves well between the graphene sheets. The quantity used should be limited, as charcoal adsorbs all compounds to some extent and could lead to a lower recovery of the desired compound. Charcoal should of course not be used if the product itself is colored.
- https://chem.libretexts.org/Courses/SUNY_Oneonta/Chem_221%3A_Organic_Chemistry_I_(Bennett)/2%3ALab_Textbook_(Nichols)/07%3A_Technique_Summaries/7.12%3A_Testing_Mixed_Solvents_for_CrystallizationProcedural summary for testing mixed solvents for crystallization.
- https://chem.libretexts.org/Courses/SUNY_Oneonta/Chem_221%3A_Organic_Chemistry_I_(Bennett)/2%3ALab_Textbook_(Nichols)/02%3A_Chromatography/2.05%3A_Gas_Chromatography_(GC)/2.5A%3A_Overview_of_GCGas chromatography (GC) is a powerful instrumental technique used to separate and analyze mixtures. A gas chromatograph is a standard piece of equipment in forensics, medical, and environmental testin...Gas chromatography (GC) is a powerful instrumental technique used to separate and analyze mixtures. A gas chromatograph is a standard piece of equipment in forensics, medical, and environmental testing laboratories .
- https://chem.libretexts.org/Courses/Martin_Luther_College/Organic_Chemistry_-_MLC/02%3A_Tools_of_Organic_Chemistry/2.01%3A_Intermolecular_Forces_(IMFs)_-_Review/2.1.05%3A_Gas_Chromatography_(GC)/2.1.5E%3A_GC_ParametersThere are many factors that affect the separation (and/or retention times) in gas chromatography, including the type of column, sample concentration, oven temperature, and flow rate of carrier gas. Th...There are many factors that affect the separation (and/or retention times) in gas chromatography, including the type of column, sample concentration, oven temperature, and flow rate of carrier gas. The factors controllable by a student are described in this section, and are related to concentration and temperature.
- https://chem.libretexts.org/Courses/SUNY_Oneonta/Chem_221%3A_Organic_Chemistry_I_(Bennett)/2%3ALab_Textbook_(Nichols)/03%3A_Crystallization/3.01%3A_Overview_of_CrystallizationThe macroscopic appearance of a crystal is a direct result of its microscopic structure, where a regular, repeating unit forms a three-dimensional crystal lattice. For this reason, there is a differen...The macroscopic appearance of a crystal is a direct result of its microscopic structure, where a regular, repeating unit forms a three-dimensional crystal lattice. For this reason, there is a difference between precipitation (the rapid formation of a solid), and crystallization (the slow growth of a solid with regular microscopic structure).
- https://chem.libretexts.org/Courses/SUNY_Oneonta/Chem_221%3A_Organic_Chemistry_I_(Bennett)/2%3ALab_Textbook_(Nichols)/05%3A_Distillation/5.03%3A_Fractional_Distillation/5.3C%3A_Uses_of_Fractional_DistillationFractional Distillation is used for both oil refining and purification of reagents and products. Fractional distillation is used in oil refineries (Figure 5.41) to separate the complex mixture into fr...Fractional Distillation is used for both oil refining and purification of reagents and products. Fractional distillation is used in oil refineries (Figure 5.41) to separate the complex mixture into fractions that contain similar boiling points and therefore similar molecular weights and properties. Gasoline, diesel fuel, kerosene, and jet fuel are some of the different fractions produced by an oil refinery.
