Ice and Boiling Water Experiment: Discover the Surprising Results

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    Boiling Ice Water
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Discussion Overview

The discussion revolves around an experiment involving ice placed in boiling water within a test tube, exploring the thermal dynamics and behavior of heat transfer in this setup. Participants examine the conditions under which the ice remains unmelted despite the boiling water above it, focusing on concepts of thermal equilibrium and convection.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant describes an experiment where ice is placed at the bottom of a test tube filled with cool water, heated from above, leading to the observation that the ice does not melt immediately.
  • Another participant challenges the assertion that the ice will not melt, suggesting that it will eventually melt at room temperature, and explains that thermal equilibrium takes time to establish due to convection processes.
  • A later reply reiterates the idea that heat rises, implying that the ice's position at the bottom contributes to the delay in melting.
  • One participant notes that if the bottom of the tube were heated instead, the convective mixing would be more efficient, potentially leading to different outcomes regarding the ice melting.

Areas of Agreement / Disagreement

Participants express varying degrees of understanding and interpretation of the experiment, with some agreeing on the role of convection in delaying the melting of ice, while others question the initial claim about the ice not melting. The discussion remains unresolved regarding the specifics of heat transfer dynamics in this scenario.

Contextual Notes

There are assumptions about the setup, such as the size of the test tube and the duration of heating, which may affect the outcomes. The discussion does not resolve the complexities of thermal transport in this context.

BL4CKCR4Y0NS
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"Ice In Boiling Water?"

If you nearly fill a test tube with cool water and then take a piece of ice and press it down on the bottom of the tube with a small weight, heat the test time with a flame that licks only the upper part of the tube, the water will start to boil sooner or later.But the ice at the bottom will not melt.

What's going on?
 
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BL4CKCR4Y0NS said:
If you nearly fill a test tube with cool water and then take a piece of ice and press it down on the bottom of the tube with a small weight, heat the test time with a flame that licks only the upper part of the tube, the water will start to boil sooner or later.But the ice at the bottom will not melt.

What's going on?

Well, first of all I don't think your last statement is strictly correct, I mean, the ice will melt eventually if you just leave it sitting out at room temperature .. you don't need the flame. However, assuming that you have a long enough tube to observe the effect you mention, all that is going on is that it takes time for the different regions to reach thermal equilibrium with each other. Thermal transport in gases and liquids takes place largely through the phenomenon of convection, where less-dense, warmer "packets" of material rise up while more-dense, cooler packets fall down, leading to mixing. In a narrow test tube, it could easily take more time for this to occur than for the water near the top of the tube to reach the boiling point.
 


Yeah I took it straight out of a book and didn't understand...

So basically it just takes more time for it to melt because heat rises and the ice is at the bottom. Yeah?
 


BL4CKCR4Y0NS said:
Yeah I took it straight out of a book and didn't understand...

So basically it just takes more time for it to melt because heat rises and the ice is at the bottom. Yeah?

Yes ... the situation would be different if you locally heated the bottom of the tube and had the ice at the top .. in that case, the convective mixing would be faster, since the heat transfer is going in the "favored" direction for convection .. sorry if that wasn't clear from the last post.
 

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