Department of Bioorganic and Biological Chemistry. Bioinorganic chemistry. I COURSE LECTURER: Professor A.D.DZHURAEV LECTURE 1. SOLUTIONS. THE DOCTRINE ABOUT SOLUTIONS. COLLIGATIVE PROPERTIES OF SOLUTIONS

PURPOSE OF LECTURES: Familiar with the general characteristics and the important properties of solutions, know the general properties of the solutions are very important for the future doctor, as in their practical work, he often deal with solutions. This is plain drinking water and liquid dosage forms, solutions of various substances used in clinical laboratories. The human body - urine slyunnnaya fluid, blood, lymph, tissue fluid, and others - all solutions. An important role in animal organisms is osmosis. Protoplasm is an ideal semipermeable membrane through which the cell can penetrate or removed from only certain substances, but it is not permeable to other substances. Since the walls of red blood cells are not permeable to NaCl, but permeable to H2O. In practice, the physician should be aware that if the body for therapeutic purposes must enter the aqueous solutions, these solutions must have an osmotic pressure of the osmotic pressure of blood plasma, ie, should be isotonic with it. The osmotic pressure of body fluids equal to the pressure of the solution 0.86% NaCl (saline). Very important concepts plasmolysis, hemolysis, turgor, izoosmiya future doctor should know exactly from chemistry course.. TMA web site:

THE LECTURE PURPOSE: Get acquainted with the general characteristic and the most important properties of solutions. To know the general characteristics of solutions is much important for future physician, as in its practical activity he often had run into the solution. This and usual drinking water, and fluid medicinal forms, solutions of different materials, used in clinical laboratory. In organism of the person - the urine, lachrymal liquid, blood, lymph, tissue liquid and others - all this are solutions. The Important role in animal organism plays the osmosis. The protoplasm of the cells presents itself the ideal semi-permeable membrane, through which in cell can penetrate or delete from it only determined substances, but she not permeable for the other substances. So, walls of erythrocytes is not permeable for NaCl, but permeable for Н2O. In practical activity physician must know that if in organism in therapeutic purpose necessary to enter the water solutions, these solutions must to have an osmotic pressure, equal to osmotic to pressure of the blood plasma, i.e. must be isotonic with her. Osmotic pressure of the liquids of the persons organism is a pressure 0,86% solution of NaCl (the physiological solution). Very important notions plasmolysis, hameolysis, turgor, izoosmiya must to know the future physician from course of the chemistry, exactly.

D EALT of questions  The object and purpose, and bioinorganic phys-colloid chemistry  Value basis and bioinorganic chemistry in medicine Phys-colloid chemistry  Solutions and general properties of solutions  Solubility and factors affecting solubility  Colligative properties of solutions  Properties of strong and weak electrolytes  TMA web site:

D EALT of questions  The diffusion process  Osmosis and osmotic pressure  Calculation of the osmotic pressure of ideal solutions based on Mendeleev-Clapeyron equation  Oncotic pressure of the solution  Saturated vapor pressure of the laws of Raul solutions  Protolytic acid-base theory  The ionic product of water, hydrogen and hydroxyl indices  TMA web site:

Clausius-Clapeyron equation: Where: N1 and N2 solubility of gases at temperatures T1 and T2? λ-, the heat on dissolution of one mole of gas in its saturated solution.? R - universal gas constant

Dependence of the solubility of gases on the pressure Henry's law  = K  P  - mass concentration of gas in a saturated solution P - gas pressure K - constant depending on the nature of the gas

Dependence of the solubility of gases in liquids from the presence of foreign material dependence of gas solubility in the liquid from the presence of foreign substances Sechenov’ s Law The presence of foreign substances in the solution reduces the solubility of gases in liquids: N lg = kC N 0

Ostwald's dilution law The degree of dissociation of the electrolyte increases weak solution if  << 1 then the К =  2 С

The activity coefficient of The activity coefficient of- the ratio of active concentration to the total concentration: f = a / c where: а – activity of the solute с - concentration f - the activity coefficient

The ionic strength of the solution The ionic strength of the solution is the value measured half the sum of the concentrations of all the works ions in the solution to the square of their charge. µ = ½ ( C 1 Z C 2 Z ….. + C n Z n 2 ) µ - ionic strength С – ion concentration Z – ion charge

Example calculation of ionic strength In 0.1 M HCl solution contains / H + / = 0.1 g-ion / l / Cl-/ = 0.1 g-ion / l. The ionic strength of the solution will be: µ = ½ ( / Н + / Z Н 2 + / СI - / Z СI 2 ) = ½ ( 0,1 * 1 + 0,1 * 1 ) = ½ * 0,2 = 0,1

Colligative properties of solutions Osmotic pressure Lowering the vapor pressure of the solvent over a solution Freezing point depression in comparison with the pure solvent Boiling point elevation compared to the pure solvent

Раствор с ахароз ы H2OH2O H2OH2O полупроницаемая мембрана One-way diffusion of solvent molecules through a semipermeable membrane (membrane) of the low concentration in the direction of greater concentration is called osmosis The phenomenon of osmosis h

Instrument for measuring the the osmotic pressure solution water Осмометр Полупрони цаемая мембрана

Osmotic pressure. Van't Hoff's law The pressure exerted by the molecules of the solvent on the vessel wall, due to their one-sided diffusion is called the osmotic pressure Van't Hoff's law: the osmotic pressure is directly proportional to the concentration of solute in solution  = CRT – for solutions of nonelectrolytes  =  CRT – for electrolyte solutions where:  - osmotic pressure, C – concentration of the solution, R –universal gas constant, T – absolute temperature,  -isotonic coefficient

The equation of Mendeleev - Clapeyron. PV=n R T V – volume of the solution n – the number of moles of solute if n\V = C and Р = Р osm, then Р osm =СRT PV = n R T Determination of the molar mass of nonelectrolytes: Р osm =СRT, if С=n\V, n=m\M Р osm = n \ V*RT, here M = m R T \ Р осм V

Solutions with different osmotic pressure isotonic solutionhypertonic solutionhypotonic solution

Plasmolysis A solution with a low concentration A solution with a high concentration of

Hemolysis A solution with a low concentration A solution with a high concentration of

Raul’s law Steam pressure at which under certain temperature comes the dynamic equilibrium, characterized by equality evaporation and condensation of liquid called the pressure of saturated steam.

Raul’s law The relative decrease of the vapor pressure of the solvent over a solution is equal to the mole fraction of the solute, that ratio of the number of moles of solute to the total number of moles of solute and solvent P 0 - P n P 0 - P n = or = P 0 n + N P 0 N Where: P 0 -P - the vapor pressure of the pure solvent P - vapor pressure of the solvent over a solution n, N - amount of substance of solute and solvent

Boiling point elevation The difference between the boiling temperature of the solution and the solvent is called the Boiling point elevation. It is directly proportional to the molal concentration of the solute:  t boiling. = E. m Где:  t boiling. –increase the boiling point E – ebullioscopic constant m – molal concentration of the solution

Ebullioscopy Ebullioscopy- shows increasing boiling one molality solution compared to the pure solvent.

Freezing point depression The difference between the crystallization temperature of the pure solvent and the solution is said to decrease the freezing point of the solution. It is directly proportional to the molal concentration of the solute:  t freezing = K. m Где:  t freezing – Lowering the freezing point; K – cryoscopic constant m - molal concentration of the solution

Cryoscopy Cryoscopy shows lowering the freezing point of the solution one molality compared to the pure solvent.

Cryoscopic method for the determination of the molar mass of nonelectrolyte ∆t freezing = K m if m = q*1000\ GM, Then ∆t зам = q- mass of solute G – weight of the solvent К – cryoscopic constant