Random thoughts thread while microwaving dinner

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Discussion Overview

The discussion revolves around the physics of microwaving food with clingfilm, particularly focusing on the behavior of air and gases within the sealed environment as it heats and cools. Participants explore the implications of temperature changes on air pressure and the role of water vapor in this process.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant suggests that the expansion of the clingfilm bubble is due to excited air molecules moving faster when heated, leading to a bulge that could pop if microwaved too long.
  • Another participant questions what happens to the air inside the bubble as it cools, speculating it may relate to water vapor.
  • A different participant notes that nitrogen, which comprises a significant portion of the air, should remain in gas state, raising questions about why it does not refill the pocket after cooling.
  • One participant proposes that some gas might have escaped from the bubble during the heating process, suggesting that a reduction in gas molecules could lead to a vacuum effect as the clingfilm reseals.
  • Another participant agrees with the idea that the water vapor could condense back into liquid, contributing to the vacuum effect as the temperature drops.

Areas of Agreement / Disagreement

Participants express various hypotheses regarding the behavior of gases and water vapor in the context of microwaving food, but no consensus is reached on the exact mechanisms at play or the fate of the nitrogen gas.

Contextual Notes

Discussions include assumptions about gas behavior, the role of temperature changes, and the potential for gas escape, but these aspects remain unresolved and speculative.

skyshrimp
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Post your drunk thoughts here (AKA, not thread worthy).

Beer induced brain fart 1.

When you microwave your dinner with clingfilm sealed over the top, the electrons in that air pocket get excited and the pocket expands (due to the air molecules moving faster right?). You get a clingfilm bulge/bubble, ready to pop if microwaved for too long.

If you take the bowl out, the air compresses so much that the clingfilm vacuums the food and becomes instantly and tightly sealed.

What happened to the air inside as it cooled slightly from that hot temp that was causing the pocket to burst? It's still virtually as hot as it was before in was heated.

I'm guessing it's something to do with water vapour.
 
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skyshrimp said:
Post your drunk thoughts here (AKA, not thread worthy).

What happened to the air inside as it cooled slightly ...

I'm guessing it's something to do with water vapour.
Good guess...
 
My drinking bender has extended to day 2 :cool:

I'll get it tomorrow on my own, but I like to test my mettle. The air pocket was filled with 78% nitrogen. Nitrogen is comprised of 3 tightly bonded atoms and should remain in gas state. The plate of food is still tightly vacuumed after it's removed from the microwaves/heat. What happened to the nitrogen and why doesn't it fill the pocket again in gas state?

I can vision the steam from the food creating the expansion of the clingfilm, but that doesn't explain the vacuum and what happened to the nitrogen.
 
skyshrimp said:
My drinking bender has extended to day 2 :cool:
The plate of food is still tightly vacuumed after it's removed from the microwaves/heat. What happened to the nitrogen and why doesn't it fill the pocket again in gas state?

I can vision the steam from the food creating the expansion of the clingfilm, but that doesn't explain the vacuum and what happened to the nitrogen.
Nitrogen gas is N2, not 3 atoms.
Just a thought: Are you certain that some of the gas didn't escape the bubble? Perhaps some hissed out at the seam between the film and the bowl? The interface could reseal as the pressure inside reduces. With less actual gas molecules inside the bubble, the pressure could drop, so that the outside pressure actually pushes in on the film, creating your vacuum.
 
I see what you're saying. It's a possibility. Some of the air might of pushed out from the edge of the clingfilm seal when the water vapour from the heated food created the bubble. When it cooled again (and the clingfilm edge is possibly sealed tight again from heat), the vapour returns to water and the space creates a vacuum.
 
We already have a "Random thoughts", so this is closed.
 
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