States of Matters and Solutions Lecture Notes PDF

Field of Pharmacy Sciences Bachelor of Pharmacy-PharmD (Clinical Pharmacy) Program Pharmaceutical Inorganic & Physical Lecture 6: States of matter and Solutions Chemistry(PMC101) Dr. Amir Shaaban Farag Date : Nov./20...

Field of Pharmacy Sciences Bachelor of Pharmacy-PharmD (Clinical Pharmacy) Program Pharmaceutical Inorganic & Physical Lecture 6: States of matter and Solutions Chemistry(PMC101) Dr. Amir Shaaban Farag Date : Nov./20 /2024  Matter that has a uniform and definite composition is called a substance.  Substances contain only one kind of matter. All samples of a substance have the same physical properties (All crystals of sucrose taste sweet and dissolve completely in water). A physical property is a quality or condition of a substance that can be observed or measured without changing the substance’s composition. Examples of physical properties include: 1. COLOR 2. SOLUBILITY 3. ODOR 4. HARDNESS 5. DENSITY 6. MELTING POINT 7. BOILING POINT  Physical properties help chemists identify a substance based on their characteristics. Schematic representations of the three states of matter. SOLIDS  Definite shape and volume.  The shape doesn’t depend on the shape of their container.  The particles are packed tightly together, they are almost incompressible.  Solids expand only lightly when heated LIQUIDS  Take the shape of their container (flows).  Particles are packed closely together, but not rigidly packed.  The volume that a liquid occupies is always constant, no matter what shape it takes.  Almost incompressible, with a tendency to expand when heated. GASES  Take the shape and form of their container (flowable).  Particles are spaced far apart.  Gases expand without limit to fill any space.  Gases are easily compressed. Phase diagrams  Most high school physics teachers describe three states of matter: solid, liquid, and gas.  Two states of matter they didn’t teach you about in school…! 1] Plasma 2] Bose-Einstein Condensate  Moreover, there are probably hundreds of matter states that are neither liquid nor solid, but something in between. Substances that inhabit these in-between states, known as liquid crystals, flow like liquids yet have optical and other properties more characteristic of crystals. - mixtures of two or more chemically non reactive substances.  Most chemical reactions are carried out in solutions.  Body fluids are also solutions of various components in water. -A mixture can be homogenous or heterogenous depending on size of the particles of the various substances. Solute: the constituent present in a smaller amount. Solvent: the constituent present in a larger amount. (If present in equal amounts, call either as solute or solvent). Concentration of a solution: The amount of solute present in a given amount of solution. True solution: the solute is dispersed uniformly throughout the solvent. e.g. solution of sugar in water. 1) Physical state 2) Unsaturated/saturated/supersaturated 3) Concentration (diluted/concentrated) 4) Miscible/immiscible 5) Electrolyte/nonelectrolyte Types of Solutions (1-Physical state) Dental amalgum filling (liquid in solid) Metal alloy (solid in solid)  (2- Degree of saturation) Another way to classify solutions is, by their capacity to dissolve a solute.  Unsaturated Solution: it contains less solute than it has the capacity to dissolve.  Saturated Solution: A solution that contains the maximum amount of a solute in a given solvent, at a specific temperature.  Supersaturated solution: contains more solute than is present in a saturated solution. This could be achieved by heating. (3-Concentration) (4-MISCIBILTY) (5-Electrolytes and non electrolyte) Electrolyte versus non Electrolyte solutes 1. Percent by weight. 2. Percent by volume. 3. Mass per volume percent 4. Mole fraction. 5. Molarity. 6. Molality. 7. Normality. N.B: 1 mole = M.wt expressed in gm N (no of moles)= wt (gm)/M.wt 1. Percent by weight (% W/W): Weight of solute Weight % = x 100 Total weight of solution Total weight = weight of solute + weight of solvent 2. Percent by volume (% V/V): volume of solute x 100 Volume % =Total volume of solution N.B. Density of solution = mass of solution / Volume of solution 3. Mass per volume percent (% W/V): mass of solute Mass per volume % = x 100 Total volume of solution 4. Mole fraction: Solution XA = number of moles of component A Total number of moles of all components N.B. Sum of mole fractions of all components in a solution equals one. XA+X B= 1 =A =B It is a ratio of no. of moles of one component to total no. of moles of all components in the solution……no units. 5. Molarity (M): No of moles of solute per liter of solution. M = no of moles of solute vol. of solution (L) Unit: mole/liter or M 6. Molality (m): No of moles of solute per kg of solvent. m = no of moles of solute mass of solvent (kg) Unit: mole/Kg or m 7. Normality (N): No of gram equivalents of solute per liter of solution. N = no of gm equivalents of solute vol. of solution (L) gm. Equivalent = wt in g eq. wt N = M x n Eq.wt= M.wt n Acid: Base: Salt: Redox: no. of replacable no. of replacable no. of cations no. of e gained Hydrogens OH or anions X its or lost by 1 valency molecule  1. Solutions of Gases in Gases -When a gas is mixed with another gas, a completely homogeneous solution results, provided they do not react chemically. -Gaseous solutions have the following characteristic properties: Completely homogenous (miscible). Don’t react chemically. Dalton’s law of partial pressure. Properties of the mixture = sum of properties of the components Molecules of gas A + molecules of gas B = A+B  Properties of the mixture = sum of properties of the components Molecules of gas A + molecules of gas B = A+B It states that in a mixture of non-reacting gases, the total pressure exerted is equal to the sum of the partial pressures of the individual gases. P Total= P1+P2+P3+ P4……… For each, P = nRT/V This law can be tested by comparing the total pressure of a gaseous mixture with the sum of the individual pressure of each gas before mixing.  2. Solutions of Liquids in Liquids  Liquid pairs which dissolve in each other at all proportions and have no saturation limits. e.g.: alcohol and water.  Liquid pairs which dissolve in each other only to certain limits. e.g.: water and ether.  Liquid pairs which don’t dissolve at all in each other. e.g.: water and benzene.  Liquids which have similar chemical structure are completely miscible.  Liquids which have different chemical structure are completely immiscible.  Partially miscible Liquids They dissolve in each other only in certain limits ex. Ether and water. They form two layers when equal volumes are shaken together. E.g.: phenol- water The two liquid layers are called “conjugate solutions”. One layer: saturated solution of water in phenol and the other layer is saturated solution of phenol in water.  Phenol will completely dissolve in a large quantity of water to form solution of phenol in water, if quantity of phenol is gradually increased, a stage is reached when a saturated solution of phenol in water is formed.  Further addition of phenol to water will result in the formation of two liquid layers.  Effect of temperature variation on the degree of miscibility a) Systems showing an increase in miscibility with rise in temperature. Eg. Phenol-Water system. b) Systems showing a decrease in miscibility with rise in temperature. Eg. Triethylamine-Water system. c) Systems showing upper and lower consolute temperature. Eg. Nicotine-Water system. -It is described by means of phase diagrams. -Phase diagrams= graphs of Temperature versus Composition at constant Pressure.