Chemistry · Lesson Worlds
Equilibrium: interactive science lab
Warm the mix and prove that a reversible reaction can lean toward products or back toward reactants.
Free · No account required · Runs in your browser
What will you learn?
Some reactions run both ways. Heat can lean the mix toward products. Cool it and reactants return. Equilibrium is a balance, not a stop.
How does the lab work?
Observe the simulation, make a prediction, change a variable, run the experiment, and explain the result. Finish with a challenge that tests your understanding.
You can change: Heat. Compare what happens and connect the result to the scientific explanation.
Try a comparison in Equilibrium
Start with the lab’s initial settings. Choose one control below, predict the result, and change that control while keeping the others fixed. Record the setting and what you observe before making a second change.
- Heat: the lab starts at 20 °C; its available range is 10–80 °C.
For a named starting condition, try Cool, Room, Hot. A preset can change several settings: check the controls before treating two presets as a one-variable comparison.
Questions to discuss during the activity
- Watch what happens. Reactants and products are both there. Watch both sides of the mix at room heat.
- Name the cause. Forward and reverse keep happening. Heat can favor one direction, so the mix leans. It never empties one side completely here. The reaction does not finish. It balances.
- Change something. Warm it and products should grow. Change heat, then shift.
- Guess before you run. If we warm the mix to 70 °C, products will… Guess what will happen, then run to check.
After your comparison, explain how the observations connect to this idea: Some reactions run both ways. Heat can lean the mix toward products. Cool it and reactants return. Equilibrium is a balance, not a stop. Name one condition you held fixed and one feature of the real world this model simplifies. A completed run is a starting point for discussion, rather than proof of mastery.
Who is it for?
Curious learners exploring chemistry. A parent or teacher can help younger learners read the instructions and discuss the results. Choose by topic and prior knowledge rather than a fixed grade level.
Is this lab free?
Yes. This interactive lab is free without signing in or a paid membership.
No app download is needed; interactive play requires JavaScript and a modern browser.
Use this activity with a learner
Families and educators · choose by prior knowledge
Learning goal: Some reactions run both ways. Heat can lean the mix toward products. Cool it and reactants return. Equilibrium is a balance, not a stop.
Before you begin: Read the controls for Heat. Make one prediction before changing a setting.
Check understanding: Ask for one observation, the evidence that supports it, and a question to investigate next.
A simulation simplifies the real world. Explain which conditions stayed fixed; a successful run alone does not demonstrate mastery.
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