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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
Water potential is defined as the chemical potential of water in a system, particularly in solutions, and is not strictly categorized as kinetic or potential energy. It is mathematically represented by the equation \(\mu_{water} = \left( \frac {\partial G}{\partial n_{water}} \right) _{S,V,n_{others}}\), where \(G\) is Gibbs Free Energy. The concept of water potential is crucial in understanding osmotic gradients, as water moves towards areas of lower water potential. Additionally, water potential can be described in terms of Gibbs free energy, indicating that it is a measure of the free energy available in a solution.
PREREQUISITESBiologists, chemists, and students studying plant physiology or cellular biology, particularly those interested in osmotic processes and energy dynamics in solutions.
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; \frac{1}{2}mv^2 = md.
Gokul43201 said:"Water potential" is nothing but the chemical potential of water in any system where water is a component (eg: in a solution).
\mu_{water} = \left( \frac {\partial G}{\partial n_{water}} \right) _{S,V,n_{others}}
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).
\mu_{water} = \left( \frac {\partial G}{\partial n_{water}} \right) _{S,V,n_{others}}
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).