1Chair of Chemistry of Biogenic Resources, Technische Universität München
1Department of Surgery and Surgical Specialties, Azienda Ospedaliero-Universitaria Policlinico di Modena, 2Department of Clinical Microbiology, Universtity of Modena and Reggio Emilia, 3Sanypet S.p.a, 4AIRMO Center Milan
1Human Development & Health Academic Unit, Faculty of Medicine, University of Southampton
1Department of Chemistry and Biochemistry, Central Michigan University, 2Department of Chemistry, University of Southern Maine
1Department of Biological Sciences, Macquarie University, 2Vital-IT group, Swiss Institute of Bioinformatics, 3Laboratory of Microbiology, University of Neuchatel
1School of Materials Science and Engineering, Nanyang Technological University, 2Centre for Biomimetic Sensor Science, Nanyang Technological University, 3School of Chemical and Biomedical Engineering, Nanyang Technological University
1School of Mechanical and Nuclear Engineering, Ulsan National Institute of Science and Technology (UNIST)
Source: Laboratory of Dr. B. Jill Venton - University of Virginia
Gas chromatography (GC) is used to separate and detect small molecular weight compounds in the gas phase. The sample is either a gas or a liquid that is vaporized in the injection port. Typically, the compounds analyzed are less than 1,000 Da, because it is difficult to vaporize larger compounds. GC is popular for environmental monitoring and industrial applications because it is very reliable and can be run nearly continuously. GC is typically used in applications where small, volatile molecules are detected and with non-aqueous solutions. Liquid chromatography is more popular for measurements in aqueous samples and can be used to study larger molecules, because the molecules do not need to vaporize. GC is favored for nonpolar molecules while LC is more common for separating polar analytes.
The mobile phase for gas chromatography is a carrier gas, typically helium because of its low molecular weight and being chemically inert. Pressure is applied and the mobile phase moves the analyte through the column. The separation is accomplished using a column coated with a stationary phase. Open tubular capillary columns are the most popular columns and have the stationary phase coated on the walls of the capillary. Stationary phases a…
Source: Vy M. Dong and Zhiwei Chen, Department of Chemistry, University of California, Irvine, CA
This experiment will demonstrate the hydrogenation of chalcone as an example of an alkene hydrogenation reaction (Figure 1). In this experiment, palladium on carbon (Pd/C) will be used as a heterogeneous catalyst for the process. A balloon will be used to supply the hydrogen atmosphere.
Figure 1: Diagram showing the hydrogenation of chalcone to 3-phenylpropiophenone. …
Organic Chemistry II
Source: Laboratory of Dr. Nicholas Leadbeater — University of Connecticut
Distillation is perhaps the most common laboratory technique employed by chemists for the purification of organic liquids. Compounds in a mixture with different boiling points separate into individual components when the mixture is carefully distilled. The two main types of distillation are "simple distillation" and "fractional distillation", and both are widely used in organic chemistry laboratories.
Simple distillation is used when the liquid is (a) relatively pure (containing no more than 10% liquid contaminants), (b) has a non-volatile component, such as a solid contaminant, or (c) is mixed with another liquid with a boiling point that differs by at least 25 °C. Fractional distillation is used when separating mixtures of liquids whose boiling points are more similar (separated by less than 25 °C).
This video will detail the fractional distillation of a mixture of two common organic solvents, cyclohexane and toluene.…
1School of Chemistry, EaStCHEM, University of Edinburgh, 2School of Biological Sciences, University of Edinburgh, 3Critical Care, NHS Lothian, Royal Infirmary of Edinburgh