Physics of paper absorbing Water -- Doesn't this decrease Entropy?

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SUMMARY

The discussion centers on the physics of paper absorbing water and its implications for entropy. Cellulose's hydrophilic properties, attributed to the polarity of its hydroxyl groups, facilitate hydrogen bonding with water, which overcomes gravitational forces. This process does not decrease entropy globally; rather, it may locally decrease entropy while increasing the overall system's degrees of freedom due to water's interaction with air pockets in the paper. The relationship between hydrogen bonding and the second law of thermodynamics is also explored, emphasizing that systems evolve towards lower potential energy states, which correlate with higher kinetic energy and increased entropy.

PREREQUISITES
  • Understanding of cellulose chemistry and hydrophilicity
  • Basic knowledge of hydrogen bonding and molecular polarity
  • Familiarity with the second law of thermodynamics
  • Concepts of potential energy and kinetic energy in closed systems
NEXT STEPS
  • Research the properties of cellulose and its interactions with water
  • Study the principles of hydrogen bonding in various materials
  • Explore the implications of the second law of thermodynamics in biological systems
  • Investigate the relationship between energy states and entropy in thermodynamic processes
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Students and professionals in physics, chemistry, and materials science, as well as anyone interested in the thermodynamic properties of water and cellulose interactions.

casparov
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Summary: doesn't this decrease entropy ?

Cellulose is known for its hydrophilic quality, which can be explained from the polarity of its hydroxyl groups.

We all know water can overcome the force of gravity through a piece of paper you put in the water.
Correct me if I'm wrong but this is a combination of adhesive + cohesive forces > gravity.

Why is it favorable for the water to form hydrogen bonds with the cellulose, why favorable to maximize those bonds? Is it because of higher electronegativity of the hydroxyls than the water molecules in the liquid?

How does it bring the system into a lower energy state?

Doesn't it also decrease entropy ? Or only in a very local way, because water found some air pockets inside the paper, therefore increasing the degrees of freedom ?

and more general how does hydrogen bonding rhyme with 2nd law of thermodynamics ?
 
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casparov said:
How does it bring the system into a lower energy state?

Doesn't it also decrease entropy ?
Energy is conserved, hence closed systems do not evolve into lower energy states. Instead, they evolve into lower potential energy states. Why? Because lower potential energy means higher kinetic energy (because total energy is conserved), and kinetic energy can take the form of thermal motion, which means higher temperature and hence higher entropy.
 
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