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5

Osmotic pressure for non-electrolytic solutes is given by $$\pi = CRT$$ where $C$ is the effective concentration of all the solutes. In our case, with multiple solutes, we simply add all their concentrations to obtain the effective concentration. This gives us $$ \begin{align} \pi_\mathrm{cell} &= 0.05RT\\ \pi_\mathrm{environment} &= 0.03RT \end{...


5

Osmotic pressure is consequence of non zero net water diffusion, which is consequence of non equal water activities on both sides of semipermeable membrane, which is consequence of the fact dissolved solutes decrease activity of water. Osmotic pressure of a free solution is formally an external pressure needed to be acting on this solution to keep ...


4

Good question, the surprising thing is that you cannot predict conductivity easily. Ammonium acetate, which is a salt of weak acid and weak base, is a comparable conductor as a salt formed by strong acid and strong base (e.g. NaCl). This is a really old table but look at the cases of a) Sodium chloride: salt of strong acid and strong base b) Sodium acetate: ...


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When a weak acid such as acetic acid is added to pure water, it does not ionize much, but sufficiently to make the solution acidic. On the other hand, when small amounts of weak acids are added to buffered solution with a pH near neutral, acidic acid dissociates almost quantitatively. So the van't Hoff factor depends on the pH. The same goes for weak bases ...


4

I couldn't resist. The osmotic pressure equation is $$Π = cRT,$$ where $Π$ is osmotic pressure in atmospheres, $c$ is molar concentration, $R = \pu{0.082057366080960 L atm mol-1 K-1}$ (exactly) and $T$ is temperature in Kelvin. In this problem, $Π = \pu{0.236 torr}$ times exactly $\pu{1 atm}/\pu{760 torr}$ and $T = \pu{(273.15 + 19.0) K}.$ So $c = \pu{1....


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In addition to Poutnik's answer, I would like to add some comments on the question: The first statement 'Osmosis of water is not diffusion of water:....' is incorrect. The cause of osmosis is simply diffusion: the solvent is able to diffuse through the semi-permeable membrane the solute is not. It is wrong to assume that diffusion occurs only in the ...


1

How does the solute produce an osomtic pressure? The solute creates a difference in the chemical potential of the solvent in two chambers separated by a selectively permeable membrane that allows passage only of the solvent. The system changes such as to reduce the imbalance in chemical potential and the only way for this to happen is by reducing the ...


1

If there is a difference in osmolarity and therefore in the osmotic pressure, water flows from solution with lower osmotic pressure to the higher one, decreasing this difference and therefore the flow itself as well. The kinetic of this process follows the first order kinetics. The flow rate is proportional to the osmotic pressure difference. Therefore, the ...


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Ultrafiltration is ongoing at any pressure, even if slowly and liquid always goes to the side with lower pressure. Reverse osmosis is ongoing only at pressure higher then osmotic pressure. At pressure lower than osmotic pressure, normal osmosis occurs and liquid flows to the side of higher pressure.


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