The Applet enables users to compose an ionic compund using radio buttons to select anion and cation. The molecular formula is displayed in the interface with data relative to the solubility of the ionic compound and its Ksp value. Solubility charts can be obtained for a selected cation or anion. Functional buttons may also be selected permitting the display of Ksp values agains a particular anion or cation.
Type of Material:
This Applet is a Simulation. It then presents numerical and graphical data relating to the solubility of salts.
Applet can be used in freshman chemistry to introduce solubility and solubility rules of ionic compounds.
No special software is needed just permission of the browser to run Java applets.
Identify Major Learning Goals:
This introduces the solubility of ionic compounds in water in terms of soliubility values (g/L) or the corresponding Ksp.
Target Student Population:
Freshman and higher school chemistry can use this.
Prerequisite Knowledge or Skills:
Solubility rules should be introduced to the student prior to using the Applet.
Evaluation and Observation
The applet is interactive. The solubility values and Ksp values calculated by the applet are quantitively correct. It is a very quick way to view trends in solubility with respect to cations and anions.
The navigation tabs do not work properly, especially the Cation Ksp and the anion Ksp do not display at all. Toggling from Anion/Cation/compound tabs require for you to sometimes refresh your browser for a proper display. Also, the data is not gridded so it is difficult to see the real values and ranges of Ksp values and solubilities (It is suspected that the vertical scale is logarithmic). In addition, the overlapping of data points and faint color schemes detract markedly from the usability.
Potential Effectiveness as a Teaching Tool
This is an excellent tool to introduce the concept of solubility to students and can also be used for chemical nomenclature. It is good that students can reflectively compose their molecules and receive feedbacks relative to the solubility and Ksp values.
The focus is not on conceptual understanding. Also, the absence of grids and the fine-ness of the size of the data points and I,D,N,U lettering detract from the sorts of quantitative information that is so much a part of teaching solubility products in freshman chemistry.
Ease of Use for Both Students and Faculty
The applet is easy to use for both students and faculty. It loads quickly and easily.
The navigation tabs do not work properly, especially the Cation Ksp and the anion Ksp not at all. Toggling from Anion/Cation/compound tabs requires you to sometimes refresh your browser for a proper display. There are NO instructions on the meaning; the user is left to experiment. A small side box giving instructions would be very helpful.
Other Issues and Comments:
This Applet is easy to use and is an excellent tool for introducing the concept of solubility to students or introducing chemical nomenclature of ionic compounds. Be aware that some of the navigation tabs provided do not work properly. Grid lines should be added abd the data point markers should be larger to aid in viewing ease. The colors of the data points should be stronger to help with visualization. The applet should be set up so that moving the cursor over a given data point will display the numerical data in a pop up associated with the mouse position. When all points are on the axis, only one color shows which is a little misleading. Some components have solubilities listed as unknown. Actually, the solubilities of all of these compounds are known, but they may be a little difficult to find.