Download to read offline
More Related Content
Similar to Unit12L00 Solution Vocab R15.ppt
Unit12L00 Solution Vocab R15.ppt
- 1.
- 2. Classification of Matter Matter Pure Substances Mixtures Homogeneous Mixtures Heterogeneous Mixtures ElementsCompounds Also called solutions Also called suspensions
- 3. Solution • A homogeneousmixture of 2 or more substances in a single physical state (phase). • Exist in all 3 phases.
- 4. Parts of aSolution • Solute = dissolved substance. • Solvent = dispersing medium.
- 5. Identify the solute andsolvent in each picture.
- 6. Solute = ?Solvent = ?
- 7. Hints to identifysolute & solvent • Solute – changes phase, substance you have less of • Solvent – substance you have the most of, maintains phase
- 8. Aqueous Solutions • Wateris the solvent. • Transition metals form brightly colored solutions.
- 9. Soluble • Soluble –capable of being dissolved. • A substance that dissolves in another substance is soluble in that substance.
- 10. Insoluble • A substancethat does not dissolve in another substance.
- 11. Amounts that candissolve • Solubility = maximum amount of 1 substance that will dissolve in a given amount of another substance. • LIMITS to the amounts of most liquid or solid solutes that will dissolve in a given solvent. • Temperature and pressure can affect solubility.
- 12. Factors that affectthe rate of dissolving • Rate of dissolving is different from the amount that will dissolve! • Rate is how fast. Several factors influence rate of dissolving. –Temperature –Stirring or Agitation –Surface Area of Solute –Amount of solute already dissolved.
- 13. Dissolving • Dissolving isa physical change. • All physical & chemical changes are accompanied by changes in energy.
- 14. Equations for Dissolving C6H12O6(s) C6H12O6(aq) NaCl(s) Na+(aq) + Cl-(aq)
- 15. source Covalent substances dissolveto produce molecules in solution.
- 16. Ionic substances dissolveto produce ions in solution. Movie: Dissolution of NaCl
- 18. Solvation • Interaction betweenthe solvent molecules and the solute particles. Solute particles are surrounded by solvent particles in the dissolving process. • Solute particles may be ions, polar molecules, or nonpolar molecules. • Solvent molecules may be polar or nonpolar.
- 19. Hydration • Specific namefor the solvent- solute interaction when the solvent is water.
- 20. Hydration of chloride ion. Alsocalled a molecule-ion interaction.
- 21. The solute- solvent interaction must begreater than the interaction between solute particles for dissolving to occur. Molecule-ion interaction
- 22. Solubility • Amount ofsolute that will dissolve in a specific solvent at a given TEMPERATURE and PRESSURE. • Determined experimentally. • Units: grams solute per 100 grams solvent
- 23. Solubility Curves ofSelected Solids Solubility traces for most but not all solids have +’ve slopes. The hotter the solvent, the more solute dissolves.
- 24. Why do weheat the water up when making rock candy?
- 25. Solubility Curves ofSelected Gases Solubility traces for all gases have –’ve slopes. Why do fish like cold water?
- 26. Why do yousee bubbles form on the side of the beaker as the water warms up? (It’s not hot enough to boil.)
- 27. Vocabulary Interlude • Miscible:two liquids that will mix in any amounts. –Water and ethanol are miscible in all proportions. • Immiscible: Liquids that cannot mix –Oil and water are immiscible.
- 28. Oil & H2Oare immiscible.
- 29. Types of Solutions Matter PureSubstances Mixtures Homogeneous Mixtures = Solutions Heterogeneous Mixtures Elements Compounds Conduct current Nonconductor
- 30. Electricity • What doyou need to conduct electricity? Mobile charged particles!!!!
- 31. Vocabulary Interlude • Electrolyte:A substance that dissolves in water to form a solution that conducts electricity. (There are ions in the solution.) • Nonelectrolyte: A substance that dissolves in water to form a solution that does not conduct electricity. (There are neutral molecules in solution.)
- 32. Electrolyte vs. Nonelectrolyte Whichsolution conducts a current?
- 33. Dilute vs. Concentrated •Tell you relative amount of solute in solvent. • Concentrated – relatively large amounts of solute. • Dilute – relatively small amounts of solute.
- 34. Which solution is themost dilute? The most concentrated? How do you know? The stronger the color, the more concentrated the solution.
- 36. Which solution is more concentrated? Moredilute? What can you say about the number of solute particles in pictures b and c? It’s the same!
- 37. Unsaturated Solution • Hasless solute than the maximum amount that will dissolve at that temperature and pressure.
- 38. Saturated Solution • Nomore solute will dissolve in it at that temperature & pressure. • Solubility = amount of solute required to form a saturated solution.
- 39. The solution issaturated when the solute stops dissolving.
- 40. Dynamic Equilibrium =Saturated Solution Microscopic level: Rate of dissolving = Rate of recrystallization. Macroscopic level: No apparent change.
- 41. Supersaturated Solution • Containsmore solute than a saturated solution. • VERY unstable. • Have to be clever to make them up. Sodium Acetate Solution Heat Pack Temperature
- 43. Testing for saturation: •Throw a crystal of the solute into the solution and see what happens.
- 44. 3 possible results: •Crystal dissolves • No apparent change in crystal • Bam! Suddenly have lots of solid solute in beaker. Unsaturated solution. Saturated solution. Supersaturated solution.
- 45. What kind ofsolution was this?
- 46. How do theterms saturated, unsaturated & supersaturated fit in with the solubility curves? • Saturated solutions have maximum solute that will dissolve at that temperature. Points on traces represent saturated solutions. • All points above a trace represent supersaturated solutions of that solute. • All points below a trace represent unsaturated solutions of that solute.
- 47. A B C D Characterize points A, B,C, D with respect to KNO3 trace using the terms dilute & concentrated, and saturated, unsaturated, or supersaturated. A = concentrated & supersaturated. D = dilute & unsaturated.
- 48. Summary of Dissolving •Occurs at the surface of the solid. • Involves an interaction between the solute and the solvent. • Interaction is called “solvation.” • If water is the solvent, the interaction is called “hydration.” • Involves changes in energy.
- 50. Solubility Information • Oftenpresented in graphs • Show the number of grams of a substance that can be dissolved in water between 0oC and 100oC. • Each trace represents a saturated solution. – The space above each trace represents supersaturated solutions. – The space below each trace represents unsaturated solutions.
- 51. Solubility Graphs • Sometraces have positive slopes; some are negative. • Most solids have a positive slope – the hotter the water, the more solute dissolves. • All gases have a negative slope – the hotter the water, the less gas dissolves. – The colder the water, the more gas dissolves.