goog guide to make dry ice bomb

Dry ice is solid carbon dioxide. At normal atmospheric pressure and temperature it sublimates (changes directly from a solid to a gas), resulting in a tremendous increase in volume. So what happens if you put dry ice in a closed container? Pressure quickly builds up and the container explodes. Dry ice is available for purchase at some large supermarkets or you may be able to ask for it at ice cream shops. (They use it to ship the ice cream.) A few pounds of dry ice will make several bombs.

Use a hammer to break the dry ice into small chunks that will fit through the neck of the bottle.
Optionally, you can lightly score the side of the bottle with a knife. This creates a weak spot where the bottle can break cleanly, rather than just having the cap blow off. Experiment to see what works best.
Insert 15-20 chunks of dry ice into the bottle. Adding more will make your bomb explode faster, but not necessarily with more force. Use a thick glove to protect your hand. Dry ice is -109.3°F and can cause frost bite very quickly.
Pour in enough water to cover the dry ice. This dramatically speeds up the sublimation. Quickly cap the bottle and toss it somewhere safe. (Away from yourself and anything else living.)
Wait for the bottle to explode. Generally it will take 10-30 seconds, but it could take longer. Be very careful about approaching or touching a bottle that hasn’t exploded. The pressure will probably keep increasing for a long time and it could blow at any moment, especially if you disturb it.