Iron into liquid nitrogen makes condensation plume

33 grams of iron are added to a plastic milk jug that is partially filled with liquid nitrogen. When the iron transfers its heat to the liquid nitrogen, the nitrogen boils to produce cold nitrogen gas. When this gas escapes the vent in the jug, water vapor in the air condenses to make water droplets that make the plume visible. When the iron is added in the form of a few large spheres with relatively low surface area, the heat transfers from the iron relatively slowly and the plume produced is smaller. When the iron is added in the form of a powder with a relatively high surface area, the heat transfers from the iron relatively quickly and the plume produced is larger.
The Bradley University Chemistry Club Demo Crew is grateful for support from the Illinois Heartland Section of the American Chemical Society and the Illinois Space Grant Consortium.