Dry ice has some unusual properties. We make it from CO2 liquid by turning it into a solid, but as soon as it is made it starts to change into CO2 gas without forming any liquid. The process of a gas forming direct from its solid when it warms up is called sublimation.
We need approx 2.2 kg of liquid to make 1 kg of dry ice and one kg of dry ice sublimes into 509 litres of CO2 gas under normal conditions (0ºC and one atmosphere pressure).
This explains why sealing a small piece of dry ice in a balloon will blow it up slowly as the ice sublimes. If you put the ice in a plastic pot with a push on lid the same process will blow off the top, but never put it in a sealed container as that can blow up explosively and cause serious injury.
In the same way that subliming ice will blow up a ballon it will also make bubbles if put in soapy warm water. Big bubbles or lots of small ones can be made, and even frozen ones. Have a look at Atomic Tom’s video and enjoy the show.