1 / 76

Regents Review

Regents Review. Unit 9 – Gas Laws Unit 10 – Solutions Unit 11 – Acids & Bases Unit 12 – Equilibrium. Gas Laws. Chapter 14. Ideal Gas. Don’t exist Model to explain behavior of all gases Review 1 mole of ANY gas occupies 22.4L of volume at STP. Kinetic Molecular Theory.

glain
Download Presentation

Regents Review

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Regents Review Unit 9 – Gas Laws Unit 10 – Solutions Unit 11 – Acids & Bases Unit 12 – Equilibrium

  2. Gas Laws Chapter 14

  3. Ideal Gas • Don’t exist • Model to explain behavior of all gases • Review • 1 mole of ANY gas occupies 22.4L of volume at STP

  4. Kinetic Molecular Theory • The particles in a gas are constantly moving in rapid, random, straight-line motion. • Gas particles have no volume compared to the volume of the gas. • No attraction between particles • All collisions are completely elastic

  5. Boyle’s Law • Relationship between pressure and volume • Constant Temperature and amount of gas • Mathematical relationships • As pressure is increasing, volume is decreasing • As pressure is decreasing, volume is increasing

  6. P V Boyle’s Law

  7. Example • The pressure of a 25 L sample is changed from 2 atm to 0.4 atm. What is the new volume of the gas? • P1V1 = P2V2 • (2atm)(25L) = (0.4atm)V2 • V2 = 125 L

  8. Charles’s Law • Relationship between volume and temperature • Constant Pressure and amount of gas • Mathematical relationships • As temperature is increasing, volume is increasing • As temperature is decreasing, volume is decreasing • Temperature must be in Kelvin

  9. V T Charles’s Law

  10. Example • A gas occupying 45L at 27°C is cooled until its volume is 15L. What is the new temperature of the gas?

  11. Gay-Lussacs'sLaw • Mathematical relationships • As temperature increases, pressure increases • As temperature decreases, pressure decreases • Also known as Gay-Lussac’s Law • Temperature must be in Kelvin

  12. P T Gay-Lussacs'sLaw

  13. Combined Gas Law • Combines Boyle’s, Charles’s, and Gay-Lussacs'sLaws together

  14. Example • A gas at 5atm is heated and compressed from 10L at 100K to 5L at 200K. What is the new pressure?

  15. Example • A gas at 2atm and 27°C occupies 10L of space. What is the new volume when it is cooled to STP?

  16. Avogadro’s Law • Equal volumes of gas at the same Temperature and Pressure have the same number of particles • At the same temperature and pressure, which sample contains the same number of moles of particles as 1 liter of O2(g)? (1) 1 L Ne(g) (3) 0.5 L SO2(g) (2) 2 L N2(g) (4) 4 L H2O(g)

  17. Ideal Gases • Ideal Gases follow assumptions of the Kinetic Molecular Theory • When do real gases act most like an ideal gas? • High Temperature • Low Pressure • When do real gases act least like an ideal gas? • Low Temperature • High Pressure

  18. Solutions and Solubility Chapters 15, 16 Reference Tables F, G

  19. Solution • Homogeneous Mixture • Uniform Throughout • Solvent • Dissolving medium in mixture • Solute • Dissolved particles in solution • Aqueous Solution • Solution with water as the solvent • NaCl(aq)

  20. Solubility • measure of the amount of solute (how much) that can dissolve in a given quantity of solvent at certain conditions • Affected by Temperature, Pressure, and Chemical Nature • Soluble • Solute will dissolve in solvent • Insoluble • Solute will not dissolve in solvent

  21. Temperature • increasing temperature increases solubility of solids and liquids in other solids and liquids • decreasing temperature increases solubility of gases in liquids • Ex: Cold soda is fizzy

  22. Pressure • Increasing partial pressure of gas above liquid increases solubility of the gas in the liquid • Example • Soda Bottles

  23. Chemical Nature • “Like dissolves Like” • Polar and ionic substances will dissolve in polar solvents • Nonpolar substances will dissolve in nonpolar solvents

  24. Dissolving Speed • Stirring • stirring increases speed of dissolving • Temperature • Increasing temperature increases speed of dissolving solids and liquids • Particle Size • decrease particle size or increase surface area, increase speed of dissolving

  25. Table G • Shows the relationship between temperature and amount of solute for a number of different compounds

  26. Types of Solution • Saturated • maximum amount of solute for a given quantity of solvent • At Equilibrium • Unsaturated • contains less than the maximum amount of solute • Supersaturated • Contains more solute than it can theoretically hold

  27. Solution Types • Saturated • On the line • Unsaturated • Under the line • Supersaturated • Above the line

  28. Electrolytes • Compounds that conduct an electrical current when dissolved or in a molten state (melted) • Ionic compounds • NaCl, KNO3, HCl

  29. Dissolving vs. Dissociation • Dissolving • Molecules separate as solvent molecules mix • C6H12O6(s) + H2O(l)  C6H12O6(aq) • Dissociation • Ions separate as solvent molecules mix • NaCl(s) + H2O(l)  Na+(aq) + Cl-(aq)

  30. Separating Mixtures • Mixtures can be separated based on their physical properties • Boiling Pt, Freezing Pt, Density, Molecular Polarity, Particle Size • Process Examples • Filtering, Distillation, Evaporation, Crystallization, Chromatography, Desalination, Extraction

  31. Molarity • Molarity = Moles of Solute Liters of Solution • 1 mol/L = 1 M • Often used for solids dissolved into liquids • Most common concentration system

  32. Molarity Example • What is the molarity of 2 moles of glucose dissolved in 5 Liters of solution? • Molarity = Moles of Solute Liters of Solution

  33. Example • How many moles of HCl are dissolved in 4L of a 3M solution of HCl? • Molarity = Moles of Solute Liters of Solution

  34. Percent Composition • Percent Comp = Part x 100% Whole

  35. Example • A solution contains 80g of NH4Cl in a 1000g solution, what is the percent by mass composition of this solution?

  36. Example • A solution contains 60 mL of NH3 in a 1 Liter solution, what is the percent by volume composition of this solution?

  37. Parts Per Million (ppm) • Used for very small concentrations • ppm = grams of solute x 1,000,000 grams of solution • Units = ppm

  38. ppm example • A 2 kg bar of silver contains 0.05 g of gold, what is the parts per million concentration of gold in the silver bar? 25 ppm Au

  39. Colligative Properties of Solutions • Properties of a solution that depend only on the number of particles dissolved • Vapor Pressure • Boiling Point • Melting Point • Added solute particles get in the way of the solvent molecules changing the above properties

  40. Colligative Properties of Solutions • Adding more solute particles to pure solvent decreases vapor pressure • Adding more solute particles to pure solvent increases boiling point • Adding more solute particles to pure solvent decreases freezing point

  41. Number of Particles • When a covalent compound dissolves the compound stays intact. • When an ionic compound dissociates the compound splits into its ions. • More particles, larger change in property

  42. Acids and Bases Chapter 19 Reference Tables K, L, M

  43. Electrolyte • A substance that conducts an electrical current when melted or in solution • Ionic compounds • Acids and bases

  44. Acid-Base Theories • Arrhenius • Acid • Compounds that ionize to produce hydrogen ions (H+) in aqueous solutions • Examples: HCl, HBr, H2SO4,CH3COOH • Base • Compounds that ionize to produce hydroxide ions (OH-) in aqueous solutions • Examples: KOH, NaOH, LiOH

  45. Acid - Base Theories • Bronsted-Lowry • Acid • Hydrogen ion donor • Base • Hydrogen ion acceptor • Lewis • Acid • Accepts a pair of electrons • Base • Donates a pair of electrons

  46. Acid-Base Theory Lewis Arrhenius Bronsted- Lowry

  47. Properties • Acids • Taste Sour • Will change color of acid – base indicator • Can be strong or weak electrolytes in an aqueous solution • Bases • Taste Bitter • Feel Slippery • Will change color of acid – base indicator • Can be strong or weak electrolytes in an aqueous solution

  48. Ionization • Electrolytes will dissociate into ions when dissolved in water • Strong Electrolytes will completely dissociate • Weak Electrolytes will only partially dissociate

  49. Ionization of Water • Water can be split into 2 ions • H+ and OH- • Ionization of Water • H2O  H+ + OH- • H2O + H2O  H3O+ + OH-

  50. Strong Acids • Completely dissociate when in solution • HCl(s) H+(aq) + Cl-(aq) • HNO3(s) H+(aq) + NO3-(aq)

More Related