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SOLUTION AND COLLOID. SPECIFIC LEARNING OBJECTIVE. At the end of the session the student should be able to explain: Definitions of Solution and Colloids System of Solutions and Colloids Type of Solutions and Colloids. SOLUTION. No.1. INTRODUCTION. Types of solution. No.2. Concentration.
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SOLUTION AND COLLOID SPECIFIC LEARNING OBJECTIVE • At the end of the session the student should be able toexplain: • Definitions of Solution and Colloids • System of Solutions and Colloids • Type of Solutions and Colloids
SOLUTION No.1 INTRODUCTION Types of solution No.2 Concentration No.3 Solution properties No.4 Dialysis No.5
SOLUTION INTRODUCTION No. 1 MATTER Definition Classification State of matter Mixture Pure substance
THE STATE OF MATTER Matter Solid Liquid Gas
CLASSIFICATION OF MATTER Matter Mixture Pure substance Homogeneous mixture Heterogeneous mixture Element Compound
HOMOGENEOUS MIXTURE Homogenous mixtures called solutions And Their distant relatives, colloidal suspensions
Solutions • Solutions are homogeneous mixtures of two or more substances in which the components are present as atoms, molecules, or ions • These uniformly distributed particles are too small to reflect light, and as a result solutions are transparent (clear) – light passes through them
SUBSTANCES OF SOLUTIONS Solutions Solute Solvent • The most abundant substance in a solution is called solvent • The substance is dissolved in a solvent is called solute
SOLUTE Solute Nonelectrolyte A solute that when dissolved in water forms a solution that does not conduct electricity. Electrolyte A solute that when dissolved in water forms a solution that conducts electricity.
HEATS OF SOLUTION Heat is usually absorbed or released when a solute dissolves in a solvent. • The process is endothermic, if heat is absorbed, and solution becomes cooler. • The process is exothermic, if heat is released, and solution temperature increases. Endothermic : Solute + Solvent + Heat Solution (NH4NO3 in water) Exothermic : Solute + Solvent Solution + Heat (NaOH in water)
SOLUTION No.1 INTRODUCTION Types of solution No.2 Concentration No.3 Solution properties No.4 Dialysis No.5
SOLUTION Types of solution No. 2 Chemical term Medical term • Unsaturated • Saturated • Super saturated • Hypotonic • Isotonic • Hypertonic
Chemical term Classification of Solubility SOLUBILITY • Three classify of solubility of a compound • 1. Soluble • 2. slightly soluble • 3. insoluble
Soluble substances dissolve completely in the solvent and form solution • Insoluble substances do not dissolve in the solvent • The term immiscible is used to describe a liquid solute that does not dissolve in a liquid solvent
Depend on the Polarity SOLUBILITY Three type of polarity of a compound : 1. Polar 2. Semipolar 3. Nonpolar 1. Soluble 2. slightly soluble 3. insoluble
UNSATURATED, SATURATED AND SUPERSATURATED SOLUTIONS • Saturated solution, is a solution that contains the maximum amount of a solute in a given solvent, at a specific temperature. • Unsaturated solution, is a solution that contains less solute that it has the capacity to dissolve. • Supersaturated solution, contains more solute than is present in a saturated solution SOLUBILITY
SUPERSATURATED SOLUTIONS • Supersaturated solutions are usually prepared by forming a nearly saturated solution at a high temperature and then slowly cooling the solution to a lower temperature at which the solubility is lower. Such solutions are not stable. The addition of small amount of solid solute (or even a dust particle) will usually cause the excess solute to crystallize out of solution until the solution becomes saturated.
CRYSTALLIZATION CONVERTS A SUPERSATURATED SOLUTION TO A SATURATED SOLUTION A supersaturated Seed crystal is added After excess solute is solution and induces rapid crystallized, the crystallization remaining solution is saturated
SOLUTION Types of solution No. 2 Chemical term Medical term • Unsaturated • Saturated • Super saturated • Hypotonic • Isotonic • Hypertonic
Medical term Hypotonic, Isotonic and Hypertonic solutions • Hypotonic solutions : the solution with the lower concentration of solute • If the concentration of water in the medium surrounding a cell is greater than that of the cytosol. Water enters the cell by osmosis • Isotonicsolutions : the solution being compared have equal concentration of solutes. • When red blood cells are placed in a 0.9% salt solution, they neither gain nor lose water by osmosis • Hypertonicsolutions : The solution with the higher concentration of solutes. • If red cells are placed in sea water (about 3% salt), they lose water by osmosis and the cells shrivel up.
Red blood cells in theHypotonic, Isotonic and Hypertonic solutions Red blood cells with hypotonic solution Red blood cells with isotonic solution Red blood cells with hypertonic solution
SOLUTION No.1 INTRODUCTION Types of solution No.2 Concentration No.3 Solution properties No.4 Dialysis No.5
SOLUTION Concentration No. 3 • Molarity (M) • Percent (%) • Molarity (M) : • a solution concentration that is expressed in term of the number of moles of solute contained in a liter of solution. • Percent : a solution concentration that expresses the amount of solute in 100 parts of solution. continued to next slide
SOLUTION Concentration No. 3 • Molality (m) • Normality (N) • Molality (m) : • a solution concentration that is expressed in term of the number of moles of solute contained in a kilogram of solvent. • Normality (N) : a solution concentration that is expresses in term of the number of gram equivalent of solute contained in a liter of solvent. continued to next slide
Continuation : • Weight/weight percent : a concentration that expresses the mass of solute contained in 100 mass units of solution. • Weight/volume percent : a concentration that expresses the grams of solute contained in 100 ml of solution. • Volume/volume percent : a concentration that expresses the volume of liquid solute contained in 100 volume of solution.
DILUTION The volumetric scales of concentration are those, like molar concentration and normality, in which the concentration is expressed on a volumetric scale, the amount of solute per fixed volume of solution, when the concentration is expressed on a volumetric scale, the amount of solute contained in a given volume of solution is equal to the product of the volume and the concentration: Amount of solute = volume x concentration continued
continued If a solution is diluted, the volume is increased and the concentration is decreased, but the total amount of solute is constant. Hence, two solutions of different concentrations but containing the same amounts of solute will be related to each other as follows: Volume1 x concentration1 = Volume2 x concentration2
continued If any three terms in the above equation are known, the fourth can be calculated. The quantities on both sides of the equation must be expressed in the same units
SOLUTION No.1 INTRODUCTION Types of solution No.2 Concentration No.3 Solution properties No.4 Dialysis No.5
SOLUTION SOLUTION PROPERTIES No. 4 Electrical conductivity and colligative properties Colligative properties (continued to next slide)
COLLIGATIVE PROPERTIES • The properties that depend only on the concentration of solute particles present and not on the actual identity of the solute. • Three closely related colligative properties are 1. Vapor pressure 2. Boiling point 3. Freezing point 4. Osmotic pressure
The equation for calculated the boiling point or freezing point difference between pure solvent and solution • Δ tb = nKbm • Δ tf = nKfm Δ t is the boiling point or freezing point difference between pure solvent and solution. Kb and Kf are constants characteristic of the solvent used in the solution.
for example : Calculate the boiling and freezing points of the following solutions • 171.0 g of sugar (C12H22O11) is dissolved in 1.00 kg of water, Kb = 0.52 0C/m and Kf = 1.86 0C/m • Answer : a. To fine the boiling point, calculate solution molality : 171.0 g (C12H22O11) 1 mol C12H22O11= 342.0 g C12H22O11 = 0.50 mol C12H22O11 m = moles of solute/1 kg of solvent = 0.50 mol/1.0 kg = 0.50 mol/kg continued to next slide x
Continuation: b. Determine n : because sugar does not dissociate upon dissolving, n = 1. c. Δ tb = nKbm = (1)(0.52 0C/m)(0.50m) = 0,26 0C d. Δ tf = nKfm = (1)(1.86 0C/m)(0.50m) = 0,93 0C
OSMOTIC PRESSURE • Is the hydrostatic pressure required to prevent the net flow of solvent through a semipermeable membrane into a solution. • Osmotic pressure () = nMRT (van’t Hoff equation) T = temperature in Kelvins R = the ideal gas constant (0.82 L-atmosphere/degree.mole) M = the solution molarity
OSMOSIS • The process in which solvent flows through a semipermeable membrane into a solution.
SOLUTION No.1 INTRODUCTION Types of solution No.2 Concentration No.3 Solution properties No.4 Dialysis No.5
SOLUTION Dialysis No. 5 • Earlier we discussed semipermeable membranes that selectively allow solvent to pass but retain dissolved solutes during osmosis. • Dialysis, another membrane process, is also important in living organisms.
Continuation • Dialyzing membranes : • A semipermeable membranes with pores large enough to allow solvent molecules, other small molecules, and hydrat ions to pass through (are semipermeable membranes with larger pores than osmotic membranes).
Continuation • Dialysis : A process in which solvent molecules, other small molecules, and hydrat ions pass from a solution through a membrane (is the passage of ions and small molecules through such membranes).
DIALYSIS.This is one method of dialysis used to purify proteins
Application of Dialysis Scheme of dialysis process Dialysate + waste product Dialysis tubing Fresh dialysate
A similar technique is used to clean the blood of people suffering kidney mal function • The blood is pumped through tubing made of a dialyzing membrane. • The tubing passes through a bath in which impurities collect after passing out of the blood. • Blood proteins and other important large molecules remain in the blood.
HEMODIALYSIS blood dialysat Scheme of hemodialysis process dialysat blood
Continuation • Dialysis is most commonly used to remove salts and other small molecules from solutions of macromolecules. During the separation and purification of biomolecules, small molecules are added to selectively precipitate or dissolve the desire molecule.
Continuation • Dialysis is also useful for removing small ions and molecules that are weakly bound to biomolecules. Protein cofactors such as NAD, FAD, and metal ions can be dissociated by dialysis. The removal of metal ions is facilitated by the addition of a chelating agent (EDTA) to the dialysate. • Minerals are bound by EDTA, these are: Ca, Fe, etc.
EDTA with Metal Ca, Fe, etc
COLLOID No.1 INTRODUCTION No.2 Types of colloid No.3 Colloid properties