Experiment 9: Calcium Carbide

date | aim | method | materials & equipment | results | conclusion

Date

15 December 2009 by Quest 2, to link in with Chapter 9 of our book.

Aim

To investigate some of the properties of calcium carbide (CaC₂).

Method

Outdoors, place a can with sealable lid on a wooden board. Place a chunk of calcium carbide in the can. Add another chunk as needed.

1. Use a pipette to drip water onto the calcium carbide.
    
2. Squirt water onto the calcium carbide and push the lid on.
    
3. Pour a small amount of water into the can and carefully light the gas coming from the can.

Safety note: Calcium carbide is very reactive and the by-products left in the can are caustic.

Materials & Equipment

• Calcium carbide, CaC₂.
• Water.

• Can with sealable lid.
• Wooden board.
• Leather gloves.
• Safety goggles.
• Lighter.

Results/Observations

1. The calcium carbide fizzed where the water hit it. A smell like Rotorua was produced.
    
2. After a few seconds the lid of the can was blown off with a loud pop.
    
3. The gas was easily ignited, producing bright yellow-orange flames that slowly died down. A lot of soot was produced by the flames.

Conclusion

• Calcium carbide readily reacts with water.
• Impurities in the calcium carbide contain sulphur.