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Methane: The simplest saturated hydrocarbon. It is a colorless, flammable gas, slightly soluble in water. It is one of the chief constituents of natural gas and is formed in the decomposition of organic matter. (Grant & Hackh's Chemical Dictionary, 5th ed)

Redox Reactions- Concept

JoVE 11144

Oxidation and Reduction

Some chemical reactions can be classified as reduction-oxidation reactions, or redox reactions. Oxidation is the process of an atom losing one or more electrons, and reduction is the process of an atom gaining one or more electrons.

Oxidation States

Each atom in a molecule has its own oxidation state or oxidation number. The oxidation state…

 Lab: Chemistry

Stoichiometry, Product Yield, and Limiting Reactants- Concept

JoVE 11141

Chemical equations represent how a chemical reaction proceeds from reactants to products through physical or chemical change using chemical formulas.

Stoichiometry is a term that describes the relative quantities of reactants and products in a chemical reaction. It is based on the Law of Conservation of Mass, which is a fundamental law that states that matter is neither created…

 Lab: Chemistry

Carbon Skeletons

JoVE 10661

The backbone of all organic compounds is a carbon skeleton. Each carbon atom can make four bonds, and as the carbon skeleton increases in length, the possibility for structural changes arises, such as ring structures, double bonds, and branching side chains.

Life on Earth is carbon-based because all of the macromolecules that make up living organisms depend upon carbon atoms. At the core of each organic molecule is a carbon skeleton to which other atoms bond. The variety of these other atoms give each molecule its unique properties. Carbon can form four bonds and only rarely becomes an ion, making it an extraordinarily flexible component of molecules. These properties make carbon an essential component of all life on Earth, and it is found in abundance found not only on this planet but throughout the Universe as well. Carbon-carbon bonds form the basis of the carbon skeleton. Hydrogen atoms readily bond to the carbon atom. Molecules that contain only hydrogen and carbon are called hydrocarbons. Hydrocarbons usually form either long chains or will have branches protruding at various points. Changing the number of bonds changes the properties of the molecule: for example, a fatty acid with a long hydrocarbon tail with one or more double bonds will behave differently than a fatty acid with no double bonds. Molecules with the same chemical formula b

 Core: Biology

Climate Change - Prep Student

JoVE 10642

Preparation for the Ice Melt, Greenhouse Gas, and Species Range Activities
To prepare for the exercise, first print enough data recording tables for students in each group. NOTE: Activities one and two can be done simultaneously, each by half of the class broken up into groups of two to four students, or by all students if desired.
If the class…

 Lab Bio

Catalytic Reactor: Hydrogenation of Ethylene

JoVE 10427

Source: Kerry M. Dooley and Michael G. Benton, Department of Chemical Engineering, Louisiana State University, Baton Rouge, LA

The hydrogenation of ethylene (C2H4) to ethane (C2H6) has often been studied as a model reduction reaction in characterizing new metal catalysts.1-2 While supported nickel is not the most active metal catalyst for…

 Chemical Engineering

Guidelines in Case of a Laboratory Emergency

JoVE 10379

Robert M. Rioux & Zhifeng Chen, Pennsylvania State University, University Park, PA

The most common laboratory emergencies include chemical spills, fire or explosion, electric shock, and personnel injuries. Most laboratory accidents occur due to poor planning or lack of attention. Therefore, it's always better to prevent accidents…

 Lab Safety

Working with Hot and Cold Sources

JoVE 10366

Source: Robert M. Rioux & Suprita Jharimune, Pennsylvania State University, University Park, PA

Working with extreme temperatures, both high and low, is an integral part of many laboratory operations. For many, mentioning a laboratory instantly evokes the mental picture of a Bunsen burner. Bunsen burners and hot plates are used…

 Lab Safety


JoVE 10348

Source: Vy M. Dong and Diane Le, Department of Chemistry, University of California, Irvine, CA

This experiment will demonstrate the use of a polarimeter, which is an instrument used to determine the optical rotation of a sample. Optical rotation is the degree to which a sample will rotate polarized light. Optically active…

 Organic Chemistry II

High-Performance Liquid Chromatography (HPLC)

JoVE 10156

Source: Dr. Paul Bower - Purdue University

High-performance liquid chromatography (HPLC) is an important analytical method commonly used to separate and quantify components of liquid samples. In this technique, a solution (first phase) is pumped through a column that contains a packing of small porous particles with a second phase bound to …

 Analytical Chemistry

Degassing Liquids with Freeze-Pump-Thaw Cycling

JoVE 5639

Source: Laboratory of Dr. Neil Branda — Simon Fraser University

Degassing refers to the process by which dissolved gases are removed from a liquid. The presence of dissolved gases such as oxygen or carbon dioxide can impede chemical reactions that utilize sensitive reagents, interfere with spectroscopic measurements, or can…

 Organic Chemistry
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