Sodium chloride osmotic pressure

Ophthalmic Dosage Forms. Ophthalmic preparations can be solutions, eg, eye drops, eyewashes, ointments, or aqueous suspensions (30). They must be sterile and any suspended dmg particles must be of a very fine particle size. Solutions must be particle free and isotonic with tears. Thus, the osmotic pressure must equal that of normal saline (0.9% sodium chloride) solution. Hypotonic solutions are adjusted to be isotonic by addition of calculated amounts of tonicity adjusters, eg, sodium chloride, boric acid, or sodium nitrate. 

Sodium is essential for the maintenance of normal heart action and in the regulation of osmotic pressure in body cells. Sodium, as sodium chloride (NaCl), may be given IV. A solution containing 0.9% NaCl is called normal saline, and a solution containing 0.45% NaCl is called half-normal saline. Sodium also is available combined with dextrose, for example, dextrose 5% and sodium chloride 0.9%. 

C12-0101. Brackish water, with a salt content around 0.5% by mass, is found in semiarid regions such as the American southwest. Assuming that brackish water contains only sodium chloride and that the ions form no ion pairs, estimate the osmotic pressure of brackish water at 298 K. 

Fluids can be classified further according to their tonicity. Isotonic solutions (i.e., normal saline or 0.9% sodium chloride [NaCl]) have a tonicity equal to that of the ICF (approximately 310 mEq/L or 310 mmol/L) and do not shift the distribution of water between the ECF and the ICF. Because hypertonic solutions (i.e., hypertonic saline or 3% NaCl) have greater tonicity than the ICF (greater than 376 mEq/L or 376 mmol/L), they draw water from the ICF into the ECF. In contrast, hypotonic solutions (i.e., 0.45% NaCl) have less tonicity than the ICF (less than 250 mEq/L or 250 mmol/L) leading to an osmotic pressure gradient that pulls water from the ECF into the ICF. The tonicity, electrolyte content, and glucose content of selected fluids are shown in Table 24—3. 

It is important that injectable solutions that are to be given intravenously are isotonic, or nearly so. Because of osmotic pressure changes and the resultant exchange of ionic species across red blood cell membranes, nonisotonic solutions, particularly if given in quantities larger than 100 mL, can cause hemolysis or cre-nation of red blood cells (owing to hypotonic or hypertonic solutions, respectively). Dextrose, sodium chloride, or potassium chloride is commonly used to achieve isotonicity in a parenteral formula. 

Van t Hoff introduced the correction factor i for electrolyte solutions the measured quantity (e.g. the osmotic pressure, Jt) must be divided by this factor to obtain agreement with the theory of dilute solutions of nonelectrolytes (jt/i = RTc). For the dilute solutions of some electrolytes (now called strong), this factor approaches small integers. Thus, for a dilute sodium chloride solution with concentration c, an osmotic pressure of 2RTc was always measured, which could readily be explained by the fact that the solution, in fact, actually contains twice the number of species corresponding to concentration c calculated in the usual manner from the weighed amount of substance dissolved in the solution. Small deviations from integral numbers were attributed to experimental errors (they are now attributed to the effect of the activity coefficient). 

Body fluids, including blood and tears, have the same osmotic pressure as that of a 0.9% w/v sodium chloride solution. Solutions having the same osmotic pressure as that of 0.9% w/v NaCl solution are said to be isotonic with blood. Solutions with a higher osmotic pressure than body fluids are called hypertonic and those with a lower osmotic pressure are called hypotonic. 

The sodium chloride equivalent of a chemical is defined as the amount of sodium chloride (in grams or grains) that has the same osmotic pressure as that of 1 g of the chemical. The sodium chloride equivalents are symbolized by the letter E. The quantities of two substances that are isotonic equivalents are proportional to the molecular weight of each multiplied by the i value of the other. Thus, if the molecular weight and i value of a given chemical are known, one can calculate the sodium chloride equivalent, E, of that chemical as follows ... 

In the prescription above, 1% atropine sulfate is ordered. The sodium chloride equivalent of atropine sulfate is 0.13 (refer to Table 8.2). This means that 1% solution of atropine sulfate has same osmotic pressure as that of 0.13% solution of sodium chloride. This solution is hypotonic. Addition of 0.77 g (i.e., 0.9 - 0.13 = 0.77) of sodium chloride per 100 mL of the 1% solution of atropine sulfate results in an isotonic solution. To determine the amount of sodium chloride required to render a given solution isotonic, the following steps may be used ... 

Systematic investigations were carried out for the preparation of cellulose acetate of D.S. 2,65 and other mixed esters which included cellulose acetate-propionate, cellulose acetate-butyrate, cellulose acetate-benzoate and cellulose acetate-methacrylate. The experimental conditions were optimised for maximum yield of the ester. Flat osmotic membranes were developed from these esters and characterised for their osmotic and transport properties. The nmmbra-nes were evaluated in a reverse osmosis laboratory test-cell using 5OOO ppm sodium chloride solution at 40 bars pressure. Table 1 presents the typical performance data of these membranes. 

If you have a class with biochemists, clearly the area of enzyme kinetics is practically mandatory. If biologists are mixed in with the biochemists, osmotic pressure is an important concept to cover carefully and a concept typically not well covered in general chemistry and in most physical chemistry texts or classes. A quick example what is a 2 Osmolar solution of sodium chloride Such concentration units are used when dispensing various saline solutions in hospitals. What is the origin of the unit A 1 M NaCl solution dissociates into two ions that would double the osmotic pressure of a non dissociating solute. Thus, the 1 M solution of NaCl becomes a 2 Osmolar solution. Other examples abound - the bursting pressure of a cell relates to the osmotic pressure of the serum in which the cell finds itself. 

Calculate the osmolar concentration and the osmotic pressure of the physiological sodium chloride solution (9gl NaCl aqueous solution). Note Its osmotic pressure should be almost equal to that of human body fluids (about 6.7 atm). 

Sodium, potassium, and chloride are electrolytes found in cow s milk for which the Food and Nutrition Board has estimated safe and adequate daily dietary intakes for infants, children and adolescents, and adults (NAS 1980A). Sodium functions in the body to maintain blood volume and cellular osmotic pressure and to transmit nerve impulses (NAS 1980A). The estimated safe and adequate daily dietary intake of sodium is 1100-3300 mg (2.8-8.4 g sodium chloride) for healthy adults (NAS 1980A). The American Medical Association, Council on Scientific Affairs (1979), suggested 4800 mg sodium per day as a tentative definition of moderation in sodium intake. 

Figure 2.9 Flux and rejection data for a model seawater solution (3.5 % sodium chloride) in a good quality reverse osmosis membrane (FilmTec Corp. FT 30 membrane) as a function of pressure [10]. The salt flux, in accordance with Equation (2.44), is essentially constant and independent of pressure. The water flux, in accordance with Equation (2.43), increases with pressure, and, at zero flux, meets the pressure axis at the osmotic pressure of seawater 350 psi...

The molecular weight of the sodium salt of alginic acid has been determined by measurements of osmotic pressure in sodium chloride solution.88 The n/C versus C curve was found to be independent of salt concentration for values between 0.2 N and 0.5 JV, and the slope of the curve was the same for a series of seven fractions with values of molecular weight between 48,000 and 186,000 (220-860 D-mannuronic acid units). Intrinsic viscosity measurements showed the coefficient a in the modified Staudinger s equation88 to be 1.0 and the approximate value of Km to be 15(10)-4. 

If you were to add 50.0 g of sodium chloride, an electrolyte (NaCl, molar mass 58.44 g), to enough water to make 1.00 L of solution, what would be the osmotic pressure of the solution at 22°C ... 

Figure 4.1 Flux and rejection data for a seawater FilmTec FT-30 membranes operating on 35,000 ppm (350 psi osmotic pressure) sodium chloride solution.2...

Saturated Hydraulic Conductivity, 393 Diffuse double layer, 367-369 Na-Ioad, 379, 410-416 ESP 379, 410-416 SAR, 197, 412 Dispersion, 414 Swelling, 103-115 Osmotic pressure, 377 Secondary Contaminants, 478, 479 Copper, 479, 488 Iron, 479, 488 Zinc, 479, 488 Foaming Agents, 488 Chloride, 488 Color, 489 Corrosivity, 489 Hardness, 489 Manganese, 489 Odor, 490 pH, 490 Sodium, 490 Sulfate, 490 Taste, 490... 

Amounts of dietary sodium in excess of the kidney s ability to dilute and to excrete it in the urine leads directly to hypertension and indirectly to coronary heart disease and stroke. Although sodium chloride is required at about 1 g day, a typical Western diet, in fact, may contain from 8 to 12 g day. If renal transport is impaired, sodium ion accumulates and the osmotic pressure of the blood rises. Dietary reduction of salt can ameliorate some but not all of the problems. A wide variety of low-salt food products is now available. 

---