🧊 Hot & cold packs: virtual chemistry experiment
Dissolving salts can absorb heat (NH₄NO₃) or release it (CaCl₂, NaOH).
▶ 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 5 g of ammonium nitrate to the left beaker (stir)
- Add 5 g of calcium chloride to the right beaker
The chemistry behind it
If breaking the crystal lattice takes more energy than hydration releases, dissolving is endothermic and the solution cools.
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 hot & cold packs experiment?
1. Add 5 g of ammonium nitrate to the left beaker (stir) 2. Add 5 g of calcium chloride to the right beaker You can run every step free in the Faradium virtual chemistry lab.
What is the chemistry behind hot & cold packs?
If breaking the crystal lattice takes more energy than hydration releases, dissolving is endothermic and the solution cools.
Can I do the hot & cold packs 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), Nitrogen (N), Oxygen (O), Sodium (Na), Chlorine (Cl), Calcium (Ca).
Molar masses you may need: NaOH.
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