Question

For a solution at atmospheric pressure kept in a beaker:-

• A. ${\Psi }_w={\Psi }_p$
• B. ${\Psi }_w={\Psi }_s+{\Psi }_p$
• C. ${\Psi }_w={\Psi }_s$
• D. ${\Psi }_w={\Psi }_w-{\Psi }_p$

Answer 1

The correct option is C ${\Psi }_w={\Psi }_s$

Water potential is the pressure developed due to the movement of water molecules. This may create hydrostatic pressure in the cells which may be positive or negative and create tension or turgor pressure in the cell. When the solution is kept at atmospheric pressure, there is no change in the hydrostatic pressure thus pressure potential (Pressure on the wall due to turgor pressure) will be equal to zero. Hence, the water potential will be equal to the solute potential (osmotic potential due to solute concentration) as there is no movement of water outside the cell.

So, the correct option is 'Ψ${}_w$ = Ψ${}_s$'.