Ice table interactive solver
Run the ICE Table Solver fullscreen
Edit the MicroSim in the p5.js editor
About this MicroSim
The solver scaffolds every stage of an ICE (Initial–Change–Equilibrium) analysis for common equilibrium systems (HI formation, PCl5 dissociation, N2O4 dimerization, and COCl2 decomposition). Students can edit initial concentrations and K values, then watch the guided mode animate rows being filled, show the K expression with substituted numbers, and display both the small-x approximation check and the quadratic formula coefficients. Practice mode hides the Change/Equilibrium rows until students click individual cells, submit values, and receive immediate correctness feedback.
How to use
- Pick a reaction preset to load stoichiometry, default initial concentrations, and a representative K value.
- Adjust initial concentrations (mol L⁻¹) or Kc as desired; all fields accept scientific notation.
- Choose Guided Solve to watch each ICE row animate, or Practice Mode to fill the cells yourself.
- Press Solve to generate the ICE table, algebra panel, approximation decision, and quadratic breakdown.
- Use Next step (guided mode) to advance manually, or click Change/Equilibrium cells (practice mode) to enter your answers and compare them to the correct values.
Classroom ideas
- Approximation audit: Have students try each reaction with both large and small K values, then discuss when the 5% rule allows the small-x approximation.
- Quadratic derivation: Pause on the algebra panel, copy the coefficients, and re-derive the quadratic on paper before revealing the MicroSim solution.
- Practice race: Put the solver into Practice Mode and project it; groups race to green out the entire Change row before time expires.
- Parameter experiments: Assign different initial concentration sets to student pairs so the class can observe how ICE solutions respond to dilution or product seeding.
Learning goals
| Item | Details |
|---|---|
| Subject area | Chemistry — chemical equilibrium |
| Grade band | High school (Grades 11–12) AP and introductory college |
| Learning objective | Students will be able to set up an ICE table, decide whether the small-x approximation is valid, and solve for equilibrium concentrations (including quadratic solutions when necessary). |
| Bloom's level | Apply / Analyze |
| Duration | 12–15 minutes (demo plus guided practice) |
| Prerequisites | Law of mass action, equilibrium constant expressions, algebraic manipulation of quadratics, significant figures |
| Assessment ideas | Quick-write explaining the approximation decision, worksheet screenshots of ICE rows, or mini-problems solved in Practice Mode |
Instructional design review
- Single objective check: “Students will be able to calculate equilibrium concentrations with ICE tables by toggling between approximation and quadratic methods.” ✔️
- Control inventory (Step 1.5):
| Control | Type | Purpose |
|---|---|---|
| Reaction preset | Dropdown | Loads stoichiometry and typical K |
| Initial concentration inputs | Number inputs (per species) | Set I row values |
| K value input | Number input | Adjust equilibrium constant |
| Mode buttons | Toggle buttons | Switch between Guided / Practice |
| Solve / Reset / Next step | Buttons | Run the solver and advance steps |
- Progressive disclosure: Approximation verdict, quadratic coefficients, and algebra appear only after Solve; practice fields stay hidden until a cell is selected.
- Cognitive load: Table rows are color-coded (blue, orange, green) and only one guided step pulses at a time.
- Accessibility checks: Font sizes ≥14 px, high-contrast borders, keyboard-focusable HTML inputs, and descriptive instructions in the control pane.
Lesson plan
Grade level
Grades 11–12 (AP Chemistry Unit 7) and introductory college equilibrium units
Duration
15-minute workstation or projection activity
Prerequisites
- Law of mass action expressions
- Comfort rearranging algebraic equations
- Ability to evaluate scientific notation on a calculator
Activities
- Instructor walk-through (5 min): Demonstrate Guided mode for H2 + I2 ⇌ 2 HI emphasizing row order and the approximation test.
- Student practice (7 min): Learners switch to Practice Mode, attempt Change/Equilibrium rows, and capture screenshots of any incorrect entries with reflections.
- Wrap-up (3 min): Whole-class debrief on when the 5% rule fails and why quadratics are unavoidable in certain systems.
Assessment
- Exit ticket: “Given PCl5 ⇌ PCl3 + Cl2 (Kc = 1.8×10⁻²) with 0.250 M PCl5, predict whether small-x works and justify.”
- Practice Mode log: Students submit the table after all cells are green plus a one-sentence explanation of the approximation verdict.
References
- Silberberg, M. Chemistry: The Molecular Nature of Matter and Change, 9th ed., McGraw-Hill, 2021 — ICE tables and equilibrium approximations.
- Brown, LeMay, Bursten. Chemistry: The Central Science, 15th ed., Pearson, 2022 — Quadratic treatments of equilibrium problems.