Osmotic pressure calculating

The osmotic pressure calculation remains simple for all dilute solutions. Statistical mechanics gives the Helmholtz free-energy... 

The osmotic pressure values given in Table 23 were obtained for 10% solutions of low-molecular povidones in water, using the equation given in Table 22. These values apply to pure povidone. As povidone contains only traces of impurities, e.g. 1 ppm vinylpyrrolidone, the osmotic pressure is hardly affected. This is confirmed by comparing the values measured for povidone K 17 with those calculated, in Table 23. The osmotic pressure calculated for a solution containing 1 ppm vinylpyrrolidone is given for reference. 

Product Concentration in water Osmotic pressure (calculated) Osmotic pressure (measured)... 

Each of these systems has special applications which require their use (e.g., mole fraction in heats of mixing calculations, and molality for osmotic pressure calculations). But none of these is in common use for the evaluation or remediation of water pollution problems. 

Problem-Solving Tip Units in Osmotic Pressure Calculations... 

Explain why molality is used for boiling-point elevation and freezing-point depression calculations and molarity is used in osmotic pressure calculations. 

Concentrations in osmotic pressure calculations, like all other colligative property calculations, are molal, not... 

Osmolarity, the molarity of particles in solution, and abbreviated osmol, is used for osmotic pressure calculations. 

Osmosis and osmotic pressure. Osmosis is the movement of solvent from a dilute solution to a more concentrated solution through a semipermeable membrane. The pressure that must be applied to the more concentrated solution to stop this flow is the osmotic pressure. The osmotic pressure, like the pressure exerted by a gas, may be treated quantitatively by using an equation similar in form to the ideal gas equation tt = MRT. By convention the molarity of particles that is used for osmotic pressure calculations is termed osmolarity (osmol). 

We then observe that the osmotic pressure in good solvent, calculated by Edwards, is smaller than the osmotic pressure calculated by Flory and Huggins (see Fig. 8.4). 

What is osmotic pressure How is osmotic pressure calculated Molarity units are used in the osmotic pressure equation. When does the molarity of a solution approximately equal the molality of the solution Before refrigeration was common, many foods were preserved by salting them heavily, and many fruits were preserved by mixing them with a large amount of sugar (fruit preserves). How do salt and sugar act as preservatives Two applications of osmotic pressure are dialysis and desalination. Explain these two processes. 

What is osmotic pressure How is osmotic pressure calculated Molarity units are used in the osmotic pressure equation. When does the molarity of a solution approximately equal the molality of the solution ... 

What is osmotic pressure How is osmotic pressure calculated Molarity units are used in the osmotic... 

We rare y come across biological membranes which are perfectly selectively permeable to the solvent and exclude solute molecules completely. However, due to small pore size of the membranes, though the movement of the solute molecules will be impeded, there will still occur a very slow diffusion of low molecular weight solutes. Let us consider a vessel filled with water and divided into two compartments (A and B) ly a porous membrane. The membrane is Impermeable to solute molecules. If a solute like sugar is now added to compartment B, water will flow from A to B because the osmotic pressure of the solution in B is greater than in A. There will also be a diffusion of sugar molecules from B to A at a very slow rate. Due to this, the effective osmotic pressure as judged by the movement of solvent from A to B will be less than the osmotic pressure calculated from the solute concentration alone. 

Table 8.3 Comparison between theoretical osmotic pressure calculated using van t Hoff s equation and the experimentally observed osmotic pressure for an aqueous solution of sucrose at two temperatures...

Located within the Project Configuration tab are two options for sea water osmotic pressure calculation methods. The designer can select either the TEOS 10 method or the more accurate Pitzer method. 

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