The chemistry applets and Virtual Chemistry Experiments web pages were written by David N. Blauch. If you encounter any bugs or technical problems, please send me the following information:
- The URL of the web page containing the error.
- The name and version of the operating system and web browser you are using.
- The version of the Java plug-in you are using.
- The specific settings or circumstances under which the problem occurs and a description of the problem.
- A copy of any error messages displayed on the JavaScript and Java consoles.
I am always eager for new ideas for chemistry applets or web pages and would appreciates any suggestions. Thanks.
Virtual Chemistry Experiments may be accessed from the Davidson College Chemistry Department web site (www.chm.davidson.edu/vce/). While the departmental server is normally available, we cannot guarantee external users will always have access to files or that the download speeds will be fast. Users may download and deploy the Virtual Chemistry Experiments files on local computers or internal network web servers.
In order to deploy files locally, designate a home directory and download the necessary archive files to the home directory. All Virtual Chemistry Experiments web pages require the common.zip archive. Archives for the desired topics (e.g., Atomic Orbitals, Gas Laws, Coordination Chemistry) should also be downloaded. For each archive, extract all files into the home directory. The common.zip archive will populate the home directory, while other archives will create subfolders containing the necessary files.
| Archive | Topics | Requirements |
|---|---|---|
| Common.zip | All pages require this archive. | |
| AtomicOrbitals.zip | Atomic Orbitals Hybrid Orbitals |
Java3D |
| Calorimetry.zip | Calorimetry | |
| CoordChem.zip | Coordination Chemistry Isomers of Complexes Crystal Field Theory Ligand Field Theory |
Java3D |
| Crystals.zip | Structure of Solids Ionic Solids Unit Cells |
Java3D |
| Equilibria.zip | Chemical Equilibria | |
| GasLaws.zip | Gas Laws | |
| KineticMolecularTheory.zip | Kinetic Molecular Theory | |
| Kinetics.zip | Chemical Kinetics | |
| MolecularOrbitals.zip | Molecular Orbital Theory Molecular Orbital Diagrams |
Java3D |
| PhaseChanges.zip | Phase Changes Phase Diagrams Heating Curves |
|
| Spectrophotometry.zip | Spectrophotometry Beer's Law |
|
| Stoichiometry.zip | Stoichiometry Carbon-Hydrogen Analysis |
The current version of the chemistry applets and Virtual Chemistry web pages requires a web browser and the Java plug-in (version 1.6.0_11 or later is recommended). The Java plug-in is part of the Java Runtime Environment (JRE). You may check whether Java is installed correctly by visiting the Test Your Java Version page on the Sun web site. In addition to testing the Java installation, you will obtain information on the installed version of Java.
The virtual chemistry web pages displaying three-dimensional content also require Java3D (version 1.5 or later). See the Java3D section below for important information regarding the use of this software.
- Tested Platforms
The Virtual Chemistry web pages have been tested with the following software:
- Windows XP Professional (version 2002, SP2), Java 1.6.0_13, Java3D 1.5.2
- Firefox 3.0
- Internet Explorer 7.0
- Pop-Up Windows
The Virtual Chemistry web pages employ pop-up windows to provide warnings, answers to questions, graphs, and other information. Some experiments will not function correctly if pop-up windows are blocked. Pop-up windows should therefore be allowed for the server hosting the Virtual Chemistry web pages (www.chm.davidson.edu or your local web site).
- Firefox 3.0
Tools | Options | Content
To allow pop-up windows from the web site hosting the Virtual Chemistry web pages, make sure the Block pop-up windows box is checked and select Exceptions .... (Alternately, one my uncheck the box, to permit pop-ups from all sites.) Enter the hosting web server (www.chm.davidson.edu or your local web server) in the box under Address of Web Site and select Allow. Click on Close to close the Exceptions dialog and then click on OK to close the Options dialog.- Internet Explorer 7.0
Tools | Pop-up Blocker
Select Pop-up Blocker settings and enter the hosting web server (www.chm.davidson.edu or your local web server) in the box under Address of Website to Allow. Click on Add and then click on Close to close the Pop-up Blocker dialog.
Virtual Chemistry Experiments providing 3D content employ Java3D. Java3D may be downloaded the Java3D web site.
- Installation
The Java3D installer will deploy Java3D in all current Java installations.
The following link tests whether Java3D is correctly installed: Test Java3D- Memory Limitations
The default configuration for Java allocates a heap space of 96 MB. Most modern computers can readily provide a substantially larger amount of memory. Java3D is memory intensive and some of the isosurfaces displayed in Virtual Chemistry Experiments are relative large. When insufficient memory is available, the web browser may simply freeze and the web page fail to load. For web pages that download several large virtual reality files, and progress counter may freeze at a specific file (the file that exhausts the available memory). Alternately, one of the following two messages may be displayed on the Java console:java.lang.OutOfMemoryErrorThe available Java heap memory may be displayed by entering m at the Java console. A free memory level at or near 0% indicates the Java Virtual Machine has exhausted its available heap space.
java.lang.reflect.InvocationTargetException
The amount of memory available to Java may be increased in the Java Control Panel. (In Windows, this is found in the Windows Control Panel.) Under the Java tab select Java Runtime Environment Settings. Find the most recent version of Java and enter -Xmx200m under the Java Runtime Parameters. The switch -Xmx200m allocates 200 MB of memory for the Java heap. Although more memory could be allocated if necessary, in my experience 200 MB is sufficient memory for any of the Virtual Chemistry Experiments.
I recommend increasing the memory available to Java applets when Java or Java3D is installed.
When a Java update is applied, check to make sure the runtime parameters have been preserved in the new version.
- Mouse Interaction
Button Action Left rotate object Center zoom control Right translate object
Physlets (Physics Applets) are small flexible Java applets designed for science education. Data Connections is a component of Physlets that permits inter-applet exchange of data and is used in many of the chemistry applets listed below. For more information on Physlets, to obtain the archives and documentation, and to read the Conditions of Use, visit the Physlet home page. A good introduction to Physlets technology is the Physlets book by Wolfgang Christian and Mario Belloni.
Virtual Chemistry Experiments and associated resources may be used and redistributed for non-commerical purposes without requesting permission from the author. Associated resources include the Chemistry Applets, Equilibria package, and resource files (e.g., VRML or molecular structure files). Derivative works and publications whose results are obtained with these resources should acknowledge David N. Blauch.
Web pages and Chemistry Applets that employ Physlets are subject to the Physlets Conditions of Use; consult the Physlets web site for these conditions. Web pages and applets that require DataGraph4_.jar, Filters4_.jar, Hydrogenic4_.jar, SGraphics.jar, STools.jar, Slider4_.jar, or Molecular4_.jar employ Physlets.
Virtual Chemistry Experiments Home Page
Send comments and feedback to David N. Blauch