General Chemistry 2 (SHS) PDF

 COMPETENCIES describe the effect of concentration on the colligative properties of solutions differentiate the colligative properties of nonelectrolyte solutions and of electrolyte solutions  NORMALITY Normality or the equivalent concentration. N= Molarity x n n= nu...

 COMPETENCIES describe the effect of concentration on the colligative properties of solutions differentiate the colligative properties of nonelectrolyte solutions and of electrolyte solutions  NORMALITY Normality or the equivalent concentration. N= Molarity x n n= number of protons performing units, hydrogen ions NORMALITY N= Molarity x n 0.15 M HCl N= 0.15 x 0.15 N 1= 1.4 M H2SO4 N= 1.4 x 2.8 2= N 2 M NaOH N= 2 x 2N 1= 0.4 M Ba(OH)2 N= 0.4 x 2 0.8 N =  NORMALITY What is the normality of a solution that contains 50g of H2SO4 dissolved in 15 L? N= M x n = 0.034M x 2 M= mol/ L = 0.068 N 50g H2SO4 1 mol X 1 H2SO4 = 0.034M x 1 98.076 g 15L 2(1.008) + 32.06 + 4(16)= 98.076 PARTS PER MILLION (PPM) PPM= g solute x 106 g solution PARTS PER MILLION (PPM) PPM= g solute x 106 g solution 4mg of NaCl is dissolved in 8 kg of water. What is the concentration of NaCl in ppm? PPM = 0.004g x =0.5 PPM 106 8000g 4mg x 1g 8k x =.004 g =8000g 1 1000g 1000mg 1 1kg Colligative Properties of Solutions Colligative Properties Colligative Property: A property that depends only upon the number of solute particles (concentration), and NOT upon their identity. Three Important Colligative Properties of Solutions: Vapor-pressure lowering Boiling-point elevation Freezing-point depression Vapor-Pressure Lowering Vapor pressure: is the pressure exerted by a vapor that is in dynamic equilibrium with its liquid A solution that contains a solute that is not easily vaporized always has a lower vapor pressure than the pure solvent. Vapor-Pressure Lowering The decrease in a solution’s vapor pressure is proportional to the number of particles the solute makes in solution. Freezing-Point Depression Why do people spread SALT on the roads in the winter?  Freezing-Point Depression The magnitude of the freezing-point depression is proportional to the number of solute particles dissolved in the solvent and does not depend upon their identity.  Freezing-Point Depression ΔT= Kf x m x i 1m NaCl = (-1.86) (1) - Kf= -1.86 ˚C/m ( 2)= 3.72˚ 5m NaCl =(-1.86) (5) - C m= mol solute ( 2)= 18.6˚C 5m AlCl3 =(-1.86) (5) -37.2˚C Kg ( 4) = solvent Boiling-Point Elevation Boiling Point: The temperature at which the vapor pressure of the liquid phase equals atmospheric pressure. Boiling-Point Elevation Boiling-Point Elevation: The difference in temperature between the boiling point of a solution and the boiling point of the pure solvent. The boiling point of a solution is higher than the boiling point of the pure solvent. Boiling-Point Elevation The magnitude of the boiling- point elevation is proportional to the number of solute particles dissolved in the solvent.  Boiling-Point Elevation ΔT = Kb x m x i 1 m NaCl = (0.51) (1) (2) = 1.02°C/ m Kb= 0.51 = (0.51) (5) (2)= 5.1°C/m 5m KI m= molality i= Van’t Hoff 10m KCL = (0.51) (10) 10.2°C/ (2)= m Assessment: FA ½ crosswise If 2 moles of CaCl2 are dissolved in 1 kg of water, by how much would the boiling point of the solution increase? (The boiling-point elevation constant for water is K_b = 0.512.  Refer ence Bayquen, A. & Peña, G., (2022). Exploring Life Through Science Series - General Chemistry 2 (SHS). Quezon City, Philippines. Phoenix Publishing House, Inc. and clarifications, Google Chat: Rellian Colita Email: [email protected] CREDITS: This presentation template was created by Slidesgo, including icons by Flaticon, and infographics & images by Freepik Please keep this slide for attribution