Skip to main content

Ice Bomb

Materials

2 liter Beaker with Water

Ice Bucket with Ice (to hold 2 liter Beaker)

Lots of dry-ice chunks

Ethanol - enough to cover cast-iron ice bomb

Safety Shield

Cast-iron Ice Bomb with Plug

Wrench

Unbreakable Pan (Metal or Plastic)

Top from Large Styrofoam Container (to cover the pan with)

Tongs - to pick up fragments of the bomb to display to the class

Thermal Gloves

Gloves and Goggles

      

Procedure

  1. Wear Safety goggles!!!!  And also do this demonstration on the cart with the shielding.
  2. Have the 2 liter beaker of water sitting in an Ice bucket with ice to get the water as cold as possible.
  3. Fill the ice bomb with ice water by immersing it in the beaker filled with very cold water. Make sure there is no air left in the ice bomb, then screw plug loosely on the bomb while it is still under water.
  4. Place a safety shield in front of the unbreakable pan.
  5. Fill the unbreakable pan to a depth of about 5cm with small chunks of dry ice. Slowly pour in the Ethanol and make a slush.
  6. Remove the bomb from the ice bath and tighten its plug all the way using the wrench. Place the bomb in the pan with the ethanol-dry ice slush, immersing it totally.
  7. Cover the box with the Styrofoam box top (or ceiling tile).  Place the wrench on top of this to hold the cover in place, and stand back.
  8. In about 1 minute the bomb should rupture into several large pieces of shrapnel. You should be able to hear it crack, and possibly see the Styrofoam cover jump. Throwing the cover up to a height of about 50cm. Display the cast-iron fragments, which are about 8 mm thick.

Note: The dry-ice ethanol bath can be prepared ahead of time - It will last a couple of hours.

      

Hazards

Do not use a glass vessel to hold the dry ice slush. When the bomb ruptures, it will break the glass.      

Caution! If the bomb does not detonate within a minute, DO NOT immediately uncover it to see what has happened. Allow the whole assembly (dry ice bath, bomb, and cover) to warm to room temperature before touching.

Ethanol is flammable so keep away from open flames.

Waste Management

Once warmed up, the ethanol can be poured back into the supply bottles for reuse.  the cast iron bomb fragments can go in the trash.