CHEM 122 1st Edition Lecture 10Outline of Last LectureI. Types of Crystalline solidsa. Ionic solidsb. Molecular solidsc. Covalent-Network solidsi. Diamond structureii. Graphite structureiii. Metallic solidsOutline of Current Lecture II. Physical porperties of solutionsa. Concentration of solutionsIII. System of Units for Dilute Solutionsa. Parts per millionb. Parts per billionc. Mole fractiond. Molaritye. MolalityIV. Solution FormationV. Solution ProcessThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best Used as a supplement to your own notes, not as a substitute.Current LecturePhysical Peroperites of Solutions:- Solutions: a homogeneous mixture uniformly mixed on the molecular level.- Alloys:solit metal solutionso and example would be bronze which is a solid solution of Cu and Sn. - Components: Substances in a solutiono Components of a solution are either solutes or solvento Usually solvent is the component in greatest amounto Solutes are the components dissolved in the solvent- Concentration of Solutions:o Concentration can either be qualitative or quantitative.o Qualitative: dilute solution (little solute) or concentrated solution (lots of solute)o Quanitative: Exact amount of solute in a solvent or solute.o Mass Percentage:Mass of solutetotal solution massx 100 %System of Units for Dilute Solutions:- Parts Per Million (ppm): Mass of solutetotal solution massx 106- Parts Per Billion (ppb):Mass of solutetotal solution massx 109- Mole Fraction:Moles solutetotal moles solution=mole fraction(XA❑)<1o Has no units- Molarity: Moles soluteliter solution=Molarity(M )o Mol/Lo Based on solution volume- Molality: Moles solutekg solution=Molality(m)o Molality is based on solven mass, measured in Mol/kg- Mass percent, ppm,ppb, mole fraction, and molality are all temperature insensitive but Molarity is tempersensitve because it is based on solution volume.Solution Formation- Driving forces for solution formation:1. Tendency toward randomness, becoming increasingly disordered2. Enthalpy change in forming a solution, releasing energy or adding energy.- Solvation: interaction of the solvent with a dissolved soluteo With water this interaction is called hydration- Hydrate: Sphere of molecules surrounding the solute.Solution Process1. Solvent molecules are separated, requiring energy an endothermic process (∆ H1¿2. Solute particles are separated, requiring an endothermic process (∆ H2¿3. The solute-solvent molecules interact, releasing energy, an exothermic process (∆ H3¿o Energy change equasion for the process:o3¿∆ HSoln=∆ H1+∆ H2+∆ H¿solution can either be exothermic∨endothermico If 3¿∆ H¿¿¿then the solution process is exothermico If 3¿∆ H¿¿¿then the solution process is endothermico If the solution process is too endothermic then the solution will not dissolve and a solution is not
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