🫧 CO₂ and limewater: virtual chemistry experiment
Marble + acid makes CO₂. Bubble it through limewater: milky, then clear again in excess.
▶ Launch this experiment freeRuns in your browser on any phone, tablet or laptop. No sign-up, no install, no chemicals needed.
What you'll do
- Add 25 mL of dilute hydrochloric acid to the marble chips
- Observe the limewater turning milky (CaCO₃)
- Keep bubbling: excess CO₂ turns it clear again
The chemistry behind it
CaCO₃ + 2HCl → CaCl₂ + H₂O + CO₂. In limewater: Ca(OH)₂ + CO₂ → CaCO₃↓ + H₂O, then CaCO₃ + CO₂ + H₂O → Ca(HCO₃)₂ (soluble).
Why do this experiment virtually?
Many school labs can't run this experiment safely or don't have the chemicals. In Faradium you set it up in seconds, repeat it as often as you like, change the amounts and see the real result: colours, gases, precipitates and temperature changes. The lab notebook records every observation with the balanced equation for your write-up.
Frequently asked questions
How do you do the co₂ and limewater experiment?
1. Add 25 mL of dilute hydrochloric acid to the marble chips 2. Observe the limewater turning milky (CaCO₃) 3. Keep bubbling: excess CO₂ turns it clear again You can run every step free in the Faradium virtual chemistry lab.
What is the chemistry behind co₂ and limewater?
CaCO₃ + 2HCl → CaCl₂ + H₂O + CO₂. In limewater: Ca(OH)₂ + CO₂ → CaCO₃↓ + H₂O, then CaCO₃ + CO₂ + H₂O → Ca(HCO₃)₂ (soluble).
Can I do the co₂ and limewater experiment online for free?
Yes. Faradium sets up the bench for you and ticks off each step as you complete it. It runs in any browser on a phone, tablet or laptop with no sign-up and no chemicals.
Chemistry in this experiment
Elements involved: Hydrogen (H), Carbon (C), Oxygen (O), Chlorine (Cl), Calcium (Ca).
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