GeoGebra

This is read-only version of the old wiki, feel free to browse it for materials. If you want to share your own materials, please use GeoGebraTube instead. You are also welcome to help us enhance the new wiki. If any questions arise, please contact the webmaster.

New GeoGebra tool boxes for chemical nomenclature at Secondary Education

In the framework of the project to adapt Geogebra for applications in other knowledge fields diffrerent from Dynamic Mathematics, new tools aiming at helping Secondary Education students to intuitively learn basic ideas on writing chemical compounds' formulas have been developed..

The ".ggb" file can be downloaded from: "ggb file"

This contribution to the development of Geogebra is based on an experience that was accomplished some years ago for the 3rd course of Spanish Secondary Education. It was about a card game. The cards were drawn and trimmed off from fine cardboards with different colours. Each card represented the name of one chemical element or ion and its oxidation number or electric charge. The cations and elements with positive oxidation number had that number written on the right hand side of the symbol.

and the anions and elements with negative oxidation number had them written on the left hand side of the symbol:

The card with the cation or element with positive oxidation number was always placed on the left hand side and the other one on the right hand side. In this way, the positive and negative electrical charges were always in front of each other like if they tried to get neutralized.

The way to play was simple. Given a chemical compound whose formula had to be written, i.e. iron(III) tetraoxosulfate(VI), the player must choose, from the set of cards, one of each one of the ions that the formula is made up of. Then if the electrical charges of both were different, another card representing the one with the lower oxidation number had to be added (tetraoxosulfate(VI) ion, in the example). Taking into account that now the negative charge would be greater than the positive one, another iron(III) ion should be added. Now, the positive charge is greater than the negative one, therefore, a new tetraoxosulphate(VI) ion had get into the game aiming at reaching electrical neutrality, what is the case in the example. It is about adding cards representing the chemical elements that the chemical compound is made up of, until achieving a neutral compound with the minimum possible number of cards.

Tools for most of the chemical elements and oxidation numbers have been created. They have been arranged in a similar way to that of the periodic table of elements with slight differences for room reasons. For instance, iron, cobalt, nickel, copper, silver and gold have been grouped in the same column. Some tools from the original GeoGebra program have been left since they can help to manipulate and delete the chemical nomenclature game cards when needed. Besides, an additional tool box has been added. It contains templates so that the teachers and students who use the program can either design by themselves the cards they need among those that they miss, or modify the existing ones if they want to. The tool bar has the following aspect:

The aditional tools for helping to draw new cards or modify the existing ones are the following:

that respectively correspond to:

- Ions or elements with positive oxidation number. - Ions or elements with negative oxidation number. - Anions for oxoacids with one oxygen atom. - Anions for oxoacids with two oxygen atoms. - Anions for oxoacids with three oxygen atoms. - Anions for oxoacids with four oxygen atoms.

The adaptation has been accomplished for the systematic nomenclature, but changing to any other nomenclature choice or correction of mistakes is very simple. It can be done as follows:

- Deploy the Tool menu. - Choose the option "Manage tools". - Change the tool name on the pop up dialogue box. - Save the changes. - Deploy the "Options" menu. - Choose the option "Save settings".

José Luis Hernández Neira; Centro Regional de Innovación y Formación "Las Acacias"; Comunidad de Madrid