Name of teaching material
Chemical formula formatting models self-made product
*The description appears by hovering the cursor over the image.
| Target |
Target Students in the third year of junior high school Students having difficulty grasping the image of particle models, such as atoms and molecules Students having difficulty grasping the concept of valence and neutral particles (not positively or negatively charged) Students having difficulty understanding diagrams Students having difficulty comprehending 3D models, such as molecular models |
|---|---|
| Disability category | visual impairment physically challenged other |
| Teaching units / Applicable scenes | science |
| Specific purposes |
Specific purposes The 3D rectangular models have a magnet or more embedded in one side. (The number of magnets is equal to the valence of the ion represented by the model. The magnets are positioned so as to reproduce positive charges attracting negative charges and repelling positive charges.) The models help students: - Understand what cations (positive ions) and anions (negative ions) are and what neutral means in terms of charge - Write chemical formulas based on valence - Think chemical reactions based on valence |
| Considerations for disability characteristics |
Considerations for disability characteristics - The models of ions have their valences specified and help clarifying the relationship between valence and chemical formula. The models facilitate students having difficulty grasping the concept of valence and its relationship with chemical formula to understand what they are and how to formulate chemical and reaction formulas based on valence. - Use of the models, which can be recognized as 2D model, instead of commercially available 3D molecular models, reduces the barriers for students who have difficulty comprehending 3D models and encourage them think using models. - Embedding magnets in the models so as to reproduce positive and negative valences with the N and S poles of a magnet, respectively, helps students feel that positive charges repel each other so are negative charges. It also facilitates them grasp the concept of “neutral” in terms of charge and recognize a combination of two or more atom models as one single unity. - The magnets are embedded so that the N poles are exposed on the right side of a positive ion (cation) model and the S poles are exposed on the left side of a negative ion (anion) model. In this way, the completed model can be read as a chemical formula. - For students with visual impairment, atomic symbols are to be embossed or engraved to facilitate them grasp what atom (ion) the model is representing. |
| Expected effects and results |
- The models of ions with their valences clarified facilitate students use the concept of valence for formulating a chemical formula and understand that compounds having an equal number of positive and negative charges are neutral. - The models guide students to formulate chemical formulas that result in neutral compounds via trial and error, instead of just memorizing individual formulas. This may lead to autonomous and cooperative learning. |
| How to use |
Preparation Prepare the models using thin rectangular solids (See the photos above). For cations (positive ions), embed one magnet or more (depending on their valence) on the right side so that the N pole is exposed. For anions (negative ions), embed one magnet or more (depending on their valence) on the left side so that the S pole is exposed. Ask students to: 1. Find the necessary ions using the name of the compound as a clue. 2. Formulate a chemical formula by arranging the ions found in 1 so that there would be no positive or negative charge left alone. *For studying chemical reactions, students can also use the models, such as rearranging ions constituting compounds before reaction into compounds formed by the reaction and investigating surplus or shortage of atom(s)/ion(s) and crystallization. |
| Related teaching materials and information |
The models described here aims at students 1) understand the bonding between a cation(s) and anion(s) intuitively, and 2) grasp the resultant model as a single compound. However, if the lesson aims at just learning how valence and chemical formula are related, there are various similar teaching aids available, including computer applications and simple cards with the positive or negative valence written on the right or left side. |
| Useful for other students | Useful for other students The model is effective for any students, regardless of with or without disabilities, to understand ionic bonds and their reactions because bonding of ions involves the concept of least common multiple plus sometimes polyatomic io |
- Informant HAYASHI Hideki, Special Needs Education School for the Physically Challenged
- Keywords science, chemistry, ion
- Created 2024-06-07 13:58:07
- Updated 2024-06-07 13:58:07