Physics:Collapsing can
Collapsing can or can crusher experiment is a demonstration of an aluminum can being crushed by atmospheric pressure. Due to the low pressure inside a can as compared to the pressure outside, the pressure outside exerts a force on the can causing the can to collapse.[1]
Explanation
The demonstration starts with boiling water inside the can. As the water is boiled, water vapor is created and fills the space inside the can which then pushes the air out.
H2O(l) → H2O(g)
Then, inverting a water vapor-filled can into a water bath causes the water vapor to rapidly condense back to liquid water. The condensation of water reduces pressure inside the can, so the higher pressure outside the can makes the can collapse.[2][3]
H2O(g) → H2O(l)
Limitation
There will be an impeding event that could occur which is water in the water bath being drawn inside the can by the reduced pressure. As a result, in a basic demonstration, only an aluminum can is able to be used since it is not very strong. Unlike other stronger can such as steel can, the aluminum can will be collapsed before the water can be drawn inside the can.[4] Nevertheless, Professor Julius Sumner Miller could make a steel drum collapse by sealing the opening of the drum after the water inside the drum boils and pouring water and ice onto the drum surface.[5]
Alternatives
Addition of sodium hydroxide to a can filled with carbon dioxide can produce a similar result.[6]
Gallery
A video of collapsing can experiment
A video of collapsing can experiment
References
- ↑ Limpanuparb, T.; Sathainthammanee, D.; Pakwilaikiat, P.; Kaewpichit, C.; Yimkosol, W.; Suwannakhan, A. (2021). "Reinterpreting Popular Demonstrations for Use in a Laboratory Safety Session That Engages Students in Observation, Prediction, Record Keeping, and Problem Solving". Journal of Chemical Education 98 (1): 191–197. doi:10.1021/acs.jchemed.9b00474. Bibcode: 2021JChEd..98..191L.
- ↑ "Air Pressure Can Crusher – Science Experiment". https://www.stevespanglerscience.com/lab/experiments/incredible-can-crusher/.
- ↑ Summerlin, L. R., James, L. E. Jr. (1987). Chemical Demonstrations: A Sourcebook for Teachers. Washington, DC: American Chemical Society. pp. 26–27.
- ↑ Shakhashiri, B. Z. (1985). Chemical Demonstrations, Vol. 2: A Handbook for Teachers of Chemistry. Madison, WI: University of Wisconsin Press. pp. 6–8.
- ↑ Lauth, L. (19 Jan 2019). "Professor Julius Sumner Miller maintains his faith in physics despite Why Is It So? near-miss". ABC News. https://www.abc.net.au/news/2019-01-19/julius-sumner-millers-faith-in-physics-why-is-it-so-1964/10562696.
- ↑ Archived at Ghostarchive and the Wayback Machine: How to Crush a Can Using Chemistry. YouTube.
External links
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