Clackamas Community College
Clackamas Community College: Alkenes
Clackamas Community College provides a great resource on alkenes. This site teaches you about the nomenclature and structure of alkenes. It also discusses the two types of isomers alkenes can form and addition reactions.
Other
Chemistry Guide: Structural Isomers
This site from Chemistry Guide defines a wide variety of isomers. Provides graphics for each. Positional and functional group isomers included.
Other
Bristol University: Structural or Constitutional Isomers
Structural Isomers are molecules which have the same molecular formula but have different connectivities (The Order They Are Put Together). Alkanes can be very simple examples of this. This pages shows a few examples.
Clackamas Community College
Clackamas Community College: Structural Formulas
This site from the Clackamas Community College has information on the importance of structural formulas for organic compounds, with examples. Includes links to more information.
Purdue University
Purdue: Structural Isomers
Definition of structural isomers. Discusses differences in atoms and formulas. Includes differences about chemical and physical properties. Links to related definitions provided.
Wolfram Research
Wolfram Science World: Isomer
This page from ScienceWorld provides a one sentence long definition of an isomer. Links are provided for additional information, such as: conformational isomer, configurational isomer, and structural isomer.
Wolfram Research
Wolfram Science World: Structural Isomer
This site from ScienceWorld provides a brief but factual definition on a structural isomer. Includes a link for additional information, and the definition has a scientific style to it.