Part 1: Engage (Anchoring Phenomenon)

Many chemical reactions can be predicted by considering only the outermost (valence) electrons of the reactants. For example, combining sodium metal and chlorine gas produces table salt — but why?

1. Observations and Questions:

• What patterns in the periodic table help predict whether two elements will react to form a stable compound?
• Generate at least two “need to know” questions about how valence electrons determine reaction outcomes.

Part 2: Explore (Simulation Investigation)

Open the Chemical Reaction Outcomes Predictor (Experimental 3D) simulation.

2. Data Collection:

• Use the left panel to add the following reactant sets and click Predict Outcome for each. Record the reactants, predicted product, and whether the simulation provided a 3D visualization or a “No Reaction” result.
  • Na + Cl
  • Mg + Cl + Cl (Mg + 2 Cl)
  • H + H + O (attempt to form H₂O)
  • C + O + O (attempt to form CO₂)
• For each trial, record:
  • Reactant counts and valence electrons
  • Predicted product formula
  • Evidence used by the simulation (valence pairing, octet rule, ionic vs covalent)

Data table: | Reactants | Valence electrons (sum) | Predicted Product | 3D View / No Reaction | Ionic/Covalent | Evidence Notes | |—|—:|—:|—:|—:|—:|

Part 3: Explain (Sensemaking)

3. Construct an Explanation:

• Use your recorded results to construct an explanation for how valence electrons and trends in the periodic table determine the numbers and types of bonds formed.
• Explain one reaction that produced a stable product and one combination that did not react, using specific evidence (electron counts, charges, or visualization from the 3D viewer).

Part 4: Elaborate/Evaluate (Argumentation & Modeling)

4. New Context Challenge:

• Propose a new combination of elements not tested above. Predict the product using valence logic, then test it in the simulation. If your prediction differs from the simulation outcome, revise your explanation and justify the revision with evidence.