Chemistry · Lesson Worlds
Reactions: interactive science lab
Warm the flask or feed it more reactant and prove that rate is how fast product appears.
Free · No account required · Runs in your browser
What will you learn?
Hotter particles meet more often, so the reaction finishes sooner. More reactant does the same. Cold, thin mixtures wait.
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: Temperature, Concentration. Compare what happens and connect the result to the scientific explanation.
Try a comparison in Reactions
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.
- Temperature: the lab starts at 20 °C; its available range is 5–80 °C.
- Concentration: the lab starts at 1; its available range is 0.3–2.
For a named starting condition, try Cold, 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. Reactant becomes product. The wait is the rate. Watch product fill at room temperature.
- Name the cause. Particles have to meet to react. Warm them and they move faster, so they meet more. Feed more reactant and there are more meetings too. Either way the flask finishes sooner. Heat makes meetings more often.
- Change something. Warm the flask and the fill should hurry. Change temperature, then mix.
- Guess before you run. If we warm the flask to 55 °C, the reaction will… Guess what will happen, then run to check.
After your comparison, explain how the observations connect to this idea: Hotter particles meet more often, so the reaction finishes sooner. More reactant does the same. Cold, thin mixtures wait. 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: Hotter particles meet more often, so the reaction finishes sooner. More reactant does the same. Cold, thin mixtures wait.
Before you begin: Read the controls for Temperature, Concentration. 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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