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chound
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Is water potential the kinetic energy or potential energy of water? Coz my textbook says it potential energy whereas another reference book says ts kietic energy
selfAdjoint said:Excuse me, is this a technical term in biology? Because normally the word potential, used by itself, means potential energy. The potential energy DIFFERENCE between a particle of water at two different heights is the mass of the particle times the height difference. If the particle then FALLS from the heigher height to the lower one, the kinetic energy (energy of motion) that it has gained at the bottom of the fall will equal the potential energy that it has lost; [tex]\frac{1}{2}mv^2 = md[/tex].
Gokul43201 said:"Water potential" is nothing but the chemical potential of water in any system where water is a component (eg: in a solution).
[tex]\mu_{water} = \left( \frac {\partial G}{\partial n_{water}} \right) _{S,V,n_{others}} [/tex]
Naturally, since G, the Gibb's Free Energy (or U, H or F, which can also be used in a definition like the one above) is intensive, the "water potential" of pure water (or pure anything else) under standard conditions is 0.
The water potential (or any chemical potential) is not an energy at all, though in some cases it is looks like one. When it does, it seems to resemble a potential energy. This is not, however, to say that it is independent of the KE of particles in the system. It isn't, as is evident if you write the definition in terms of the Helmholtz Free Energy, F(T,V,{n}).
For an equeous solution, the water potential is given by (if you're not too picky about accuracy) the slope of the graph of standard enthalpy of dilution as a function of the mole fraction of water (though usually, the graph is drawn with respect to the mole fraction of the solute).
Gokul43201 said:"Water potential" is nothing but the chemical potential of water in any system where water is a component (eg: in a solution).
[tex]\mu_{water} = \left( \frac {\partial G}{\partial n_{water}} \right) _{S,V,n_{others}} [/tex]
Naturally, since G, the Gibb's Free Energy (or U, H or F, which can also be used in a definition like the one above) is intensive, the "water potential" of pure water (or pure anything else) under standard conditions is 0.
The water potential (or any chemical potential) is not an energy at all, though in some cases it is looks like one. When it does, it seems to resemble a potential energy. This is not, however, to say that it is independent of the KE of particles in the system. It isn't, as is evident if you write the definition in terms of the Helmholtz Free Energy, F(T,V,{n}).
For an equeous solution, the water potential is given by (if you're not too picky about accuracy) the slope of the graph of standard enthalpy of dilution as a function of the mole fraction of water (though usually, the graph is drawn with respect to the mole fraction of the solute).
Water potential is a measure of the potential energy of water in a system. It is the driving force for water movement and is affected by factors such as solute concentration, pressure, and gravity.
Water potential can be both kinetic and potential energy. The movement of water molecules is a form of kinetic energy, while the potential energy is due to the concentration differences and other forces affecting the movement of water.
Water potential is typically measured in units of pressure, such as megapascals (MPa) or kilopascals (kPa). It can be measured using instruments such as a pressure chamber or a psychrometer.
Water potential is affected by three main factors: solute concentration, pressure, and gravity. Solute concentration, or the amount of dissolved particles in a solution, decreases water potential. Pressure, such as atmospheric pressure or pressure from cell walls, can increase or decrease water potential. Gravity also plays a role in water potential, with water moving from high to low elevations.
Water potential is crucial for plant growth as it affects the movement of water and nutrients within the plant. If soil has a lower water potential than the plant's roots, water will move from the plant into the soil, causing the plant to wilt. On the other hand, if the plant's roots have a lower water potential than the surrounding soil, water will move into the plant, allowing it to thrive.