Genie in a Bottle
· 2 liter soda bottle (or other container -beaker, flask, etc), goggles, spatula, mortar and pestle
- 30% hydrogen peroxide, manganese dioxide, it's catalytic effect is greatest if it is freshly ground within 24 hours of use.
Presentation
- Pour 50-100 mL of 30% hydrogen peroxide into 2 liter bottle (enough to cover the "dimples") or container.
- Add a pea-sized amount of manganese dioxide to bottle or container.
- Gaseous oxygen will be emitted from the bottle. The reaction is exothermic; the soda bottle will get hot and shrink slightly.
- 2H2O2 (g) + MnO2 (s) --> 2O2(g) + 2H2O (g) + MnO2 (s) + Heat
Chemiluminescent Ammonia Fountian
Requirements
Weighing balance
Ammonia solution, NH3 (aq), concentrated ‘880’
2 x 1 dm3 conical flasks
Round bottomed flask (strong),
0.2 g luminal*
Volume between 500 cm3 and 2 dm3
4 g sodium carbonate, Na2CO3
Stirring rod
24 g sodium hydrogen carbonate, NaHCO3
Plastic syringe to set up the apparatus in the diagram
0.5 g ammonium carbonate, (NH4)2CO3
Assorted bungs and delivery tubes
0.4 g copper sulphate, CuSO4
50 cm3 hydrogen peroxide, H2O2, 3%
Safety screen
Access to a fume cupboard
Eye protection
Presentation
1. Set up the apparatus as shown in the diagram, behind a safety screen or in a
Fume cupboard.
2. Prepare solution A: Dissolve 4 g Na2CO3 in 500 cm3 of water and add
0.2 g luminal. Stir to dissolve. Add 24 g NaHCO3, 0.5 g (NH4)2CO3 and 0.4 g
CuSO4. Stir well until all the solids dissolve. Dilute to 1 dm3 with water.
Fill one of the conical flasks with this solution.
3. Prepare solution B: Dilute 50 cm3 of 3% H2O2 to 1 dm3 with distilled water.
Fill the other conical flask with this solution.
4. Fill the round bottomed flask with NH3 gas in one of two ways.
Either swill a small amount of concentrated ‘880’ ammonia (approx. 1 cm3)
Around the flask. Take great care with this.
Or heat the concentrated ‘880’ ammonia in another flask to which you have
Attached a delivery tube. Fill the round bottomed flask from this flask for about
5 minutes to ensure that it contains a good supply of gas.
5. Fill the syringe with water.
6. Turn off the lights and darken the room if possible.
7. Inject several cm3 of water from the syringe into the ammonia-filled flask.
This starts the reactions.
8. By increasing the concentration of H2O2 or the amount of luminal, the
Chemiluminescence increases.
