The IrYdium Project site is a site hosted by Carnegie Mellon University and provides a collection of Java based applets that simulate chemical interactions.
The premier applet for the site is the Virtual Lab, which is an extensive applet that simulates activities that take place in a chemistry laboratory. There is a stockroom where the user can checkout solutions, glassware, pipettes, burettes and Bunsen burners. There is a workbench where solutions can be mixed, diluted and titrated. There are also panels that provide information about a selected solution, including the identities and concentrations of the solute components, the pH and the temperature. The Virtual Lab provides an array of example homework problems, each with a detailed description of a problem that can be investigated using the Virtual Lab along with a stockroom stocked with the appropriate reagents and supplies for attacking the problem. In addition to the applets, the site provides informational resources on the philosophical approach taken in developing the applets and on incorporating them into a curriculum. The students targeted are those taking introductory chemistry courses at the college level. The IrYdium Project represents the fruits of a project that has received over $1 million in funding from a collection of sources including the National Science Foundation, the Howard Hughes Medical Institute and Carnegie Mellon University. The site also provides a useful list of links to similar efforts being carried out by others
Type of Material:
The primary focus of the site is the Virtual Chemistry Lab, which is a highly interactive Java applet that simulates a chemistry laboratory. It provides glassware and a large stock of common chemical reacgents that can be used to carry out a wide rage of titration type experiments
Virtual Lab can be used by instructors to demonstrate the procedures and results of titration experiments. It can be used by students in pre- and post-lab activities of predict or analyze the results of experiments which they carry out in the lab.
Because the applets are Java based there is a wide range of results obtained when viewing them with different combinations of operating systems and browsers. This reviewer found that using Internet Explorer under Windows 2002 worked consistently well. On the other hand, the results were quite varied when using a variety of different browsers (Netscape 4.7, 6.2 and 7.0, Internet Explorer 5.2, OmniWeb 4.1 and Safari 1.0 beta) under Mac OS 9 and Mac OS X. For Mac OS X it is important to use a release of the Java Runtime Engine that is Java 2 Standard Edition v 1.3.1 or later. For Mac OS X, the most consistent results are currently obtained by using the Netscape 7.0 or Safari browsers, or alternatively, the Applet Launcher application that comes with the operating system, instead of a browser.
Identify Major Learning Goals:
The stated goal of the site is to provide faculty with Web-based tools that they can use to help students become more engaged in their chemistry studies and to better connect with chemical concepts. While the main aim is to learn the fundamental concepts of general chemistry (Thermodynamics, acid-base chemistry, stoechiometry, equilibria, solubility, among many) through experimentation which could be of a directed inquiry nature.
Target Student Population:
This site is most appropriate for students taking a course in high school chemistry or at the university level, a coure in general chemistry or quantitative analysis.
Prerequisite Knowledge or Skills:
An introduction to acids and bases and pH titrations as well as the function of common glassware and what item is appropriate for a given process - i.e. when does one use a pipet,
or a volumentric flask, etc.
Evaluation and Observation
The quality of applets is good. The Stoichiometry and Equilibrium applets provide a simple yet effective way to investigate the concentrations of the reactants and products in a small set of chemical reactions. The Virtual Lab also works very well in allowing the user to simulate laboratory activities. For example, a user can perform an acid/base titration by first checking out the desired acids and bases from the stockroom along with an indicator and pipettes and burettes for dispensing and mixing solutions. The user must manually perform each step in the procedure. When pouring or dispensing liquids from the burette there is very creative control for pouring liquids that nicely simulates how it is actually done in the lab. When using the burette the user can read the burette in the same way that they would do it in the lab. for example, I really appreciated the gradual change in indicator color as I performed a titration. I added 0.01 mL at a time and the progressive change in color was well done as was the accompanying pH meter. At any point in an experiment, a solution can be selected to query the pH and concentrations of the solute components. The Virtual Lab works very well as an adjunct to homework problems and pre-lab assignments.
It would be nice if more reactions were available for the Stoichiometry and Equlibrium applets.
Potential Effectiveness as a Teaching Tool
The applets found at the IrYdium Program site, particularly the Virtual Lab site, can be very easily incorporated into a General Chemistry or Quantitative Analysis Curriculum. As the authors make clear, the intent of the applets is not to replace traditional methods of predicting the outcome of chemical reactions,
but rather to confirm the outcome of those calculations by simulating in a fairly realistic and engaging way, how those reactions are carried out in a chemistry laboratory.
Instructors should initially introduce students to this software in either a classroom setting or else using a TA to demonstrate the site and its potential in a computer lab.
Ease of Use for Both Students and Faculty
The interface for the Virtual Lab applet is very intuitive and well documented. The other applets are less well documented and therefore less intuitive to use. Most of the applets are simulations that provide consistent and appropriate feedback. For the combinations of operating systems and browsers for which the applets work, they do work well.
See the caution above.
If run as an applet, there is a significant startup time as the system loads. If run in stand alone mode, the startup is virtually instantaneous.
The Virtual Lab Step-by-Step Demonstration print material could be made a little clearer. Thus in the "Local Homework" box, why not highlight "Step by Step Demonstration" or use this term rather than "select the sample problem"? Why do I have to choose a volume when I use a disposable pipet? Why do I have to choose a volume when I empty either it or any other pipet? The print material uses "pipette" whereas the software uses "pipet" - there needs to be conformity. Titrate with volumes of ~0,5 mL will not enable one to see "a slight color change" Get down to 0.05 mL and then to 0.01 mL and one will see a great demonstration of the color/pH change.
Other Issues and Comments:
The Virtual Lab is an excellent example of what I believe the MERLOT project is trying to promote in terms of web-based learning objects that can be used to augment a wide range of learning activities.