Q: What’s happening here?

A: The Biochemistry Club delighted kids of all ages with a CO₂ bubble demonstration at Spring Fest 2023. Bubbles were created by adding dry ice (solid CO₂) to a flask with some water, which speeds up sublimation — the process of a solid skipping liquid form and transitioning straight to a gas. A tube connected to the flask captures the escaping gas, which expands into a bubble when the other end of the tube is dipped in soapy water. When it pops, the foggy CO₂ gas appears to fall off the hand, because CO₂ is heavier than air.