Hydostatic versus Osmotic Pressure

[reising1]

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Here's a question:

A swimming pool is filled with pure water and the hydrostatic pressure at a certain depth is measured at 2.5x10^4 Pa. Salt is added to the water in the pool. After the salt dissolves, the pressure will be equal to:
Answer: the hydrostatic pressure only

What exactly is hydrostatic pressure? Is that just the normal pressure (P = pgh) at the bottom of the pool? And what about osmotic pressure in this case? Don't we have to consider the pressure from the solute (pi = imRT)?

 

[RyanRt]

You wouldn't consider osmotic pressure unless there is a semipermeable membrane between the pool and something else.

 

[Patassa]

Osmotic pressure only exist where there is a solute concentration gradient, in this case the entire pool has the same ion concentration, so there is no gradient.

 

[Cottoneyebob]

Here's a question:

A swimming pool is filled with pure water and the hydrostatic pressure at a certain depth is measured at 2.5x10^4 Pa. Salt is added to the water in the pool. After the salt dissolves, the pressure will be equal to:
Answer: the hydrostatic pressure only

What exactly is hydrostatic pressure? Is that just the normal pressure (P = pgh) at the bottom of the pool? And what about osmotic pressure in this case? Don't we have to consider the pressure from the solute (pi = imRT)?

Hydrostatic pressure is P=pgh+atm. Osmatic pressure doesn't exist in this case because their isn't a gradient.