Chemistry · Lesson Worlds
Electrolysis: interactive science lab
Raise the voltage and prove that electricity can split water into bubbles of gas.
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What will you learn?
Electrolysis uses electric energy to break a compound. More voltage, livelier bubbles — until the water is split.
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: Voltage. Compare what happens and connect the result to the scientific explanation.
Try a comparison in Electrolysis
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.
- Voltage: the lab starts at 2 V; its available range is 0.5–12 V.
For a named starting condition, try Trickle, Room, Fizz. 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. Bubbles mean gas is leaving the water. Watch a quiet fizz at 2 V.
- Name the cause. Water is H2O. Enough voltage pulls it apart into hydrogen and oxygen gas. The rods are doors for charge. The bubbles are the proof. Electricity can break a compound.
- Change something. Raise volts and the fizz should grow. Change voltage, then power.
- Guess before you run. If we raise voltage to 9 V, the bubbles will… Guess what will happen, then run to check.
After your comparison, explain how the observations connect to this idea: Electrolysis uses electric energy to break a compound. More voltage, livelier bubbles — until the water is split. 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: Electrolysis uses electric energy to break a compound. More voltage, livelier bubbles — until the water is split.
Before you begin: Read the controls for Voltage. 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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