Concept:Pure water has a maximum water potential of zero. Adding solutes creates a negative potential.
Formula:$$ \Psi_{w} = \Psi_{s} + \Psi_{p} $$
Solution:- Adding salt (a solute) to water decreases the free kinetic energy of the water molecules.
- This causes the overall water potential (\( \Psi_{w} \)) to decrease (become more negative).
- Because the solute concentration has increased, the magnitude of the osmotic pull increases. This means the osmotic potential (which is technically a negative value, \( \Psi_{s} \)) increases in absolute magnitude (or simply, the potential for osmosis increases).
Note: In many older curricula, "osmotic potential" is used interchangeably with osmotic pressure, which increases. While technically \( \Psi_{s} \) becomes more negative, the "pulling power" increases.
Why other options are incorrect:- Water potential definitively decreases, making option A incorrect.
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