Can capillary action lift water to 10 meters?

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    Capillary Limit
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Discussion Overview

The discussion centers on the feasibility of lifting water to a height of 10 meters through capillary action, exploring the mechanisms involved in water transport in trees and the role of negative pressure. It includes theoretical considerations and references to biological systems.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant questions whether achieving a 10 m elevation through capillary action is feasible, suggesting that the capillary diameter may need to be smaller than water molecules.
  • Another participant argues that while water reaches the tops of 100 m tall trees, it is not solely due to capillary action, citing negative pressure (tension) at the top of the tree as a contributing factor.
  • A participant elaborates that water in trees exists in a metastable supercooled state and could boil under negative pressure if a nucleation seed is introduced.
  • It is noted that the tiny pores in leaves create sufficient capillary action to balance the weight of the sap column, while the thicker xylem tubes cannot achieve the same effect due to their larger diameter.
  • References to external resources, including a video and a research paper, are provided to support various claims regarding capillary action and water transport in trees.

Areas of Agreement / Disagreement

Participants express differing views on the role of capillary action in lifting water to significant heights, with some emphasizing the importance of negative pressure and others focusing on the limitations of capillary action alone. The discussion remains unresolved regarding the exact mechanisms at play.

Contextual Notes

Participants mention the need for further exploration into the mechanisms of sap rise in trees and the limitations of capillary action in wider xylem tubes versus smaller leaf pores.

Yuri B.
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Is it feasible to achieve elavation of water to, let's say, 10 m height due to the capillary action effect ? Or the capillary diameter for that to achieve should be less than the water molecules themselves ?
 
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I do not believe that it is pure capillary action, but water does reach the top of 100m tall trees.
 
Integral said:
I do not believe that it is pure capillary action, but water does reach the top of 100m tall trees.

That happens due to negative pressure at the top of the tree (otherwise known as tension). You might think a liquid cannot have negative pressure but that would be wrong. Water is actually in a metastable supercooled state at the top of the tree and would boil (due to negative pressure) if a nucleation seed was provided.

Watch Veritassium's youtube video titled "The Most Amazing Thing About Trees" for a clear explanation.
 
Integral said:
I do not believe that it is pure capillary action, but water does reach the top of 100m tall trees.
The pores of the leaves (where the water evaporates) are indeed so tiny (2-5 nm), that capillary action is strong enough to balance the weight of the sap column below, within which the force is transmitted as tension (negative pressure) in the much thicker xylem-tubes (20000-200000 nm).

https://www.youtube.com/watch?v=BickMFHAZR0
 
I meant artificial material.
 
:
"...venerable question of why sap rises in tall trees [32]. We
hope to address this problem in future work"
 
Yuri B. said:
:
"...venerable question of why sap rises in tall trees [32]. We
hope to address this problem in future work"

See post #4. The xylem tubes in the tree stem are too wide to pull the water 100m by capillary action. But the much smaller pores in the leaves provide enough capillary action to balance the weight of the fluid column below, which is under tension.
 

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