Chapter 14 pt 2
Chapter 14 pt 2 CHEM 1200
Popular in Chemistry II
Popular in Chemistry
This 2 page Class Notes was uploaded by Alexi Martin on Friday February 26, 2016. The Class Notes belongs to CHEM 1200 at Rensselaer Polytechnic Institute taught by Dr. Alexander Ma in Spring 2016. Since its upload, it has received 25 views. For similar materials see Chemistry II in Chemistry at Rensselaer Polytechnic Institute.
Reviews for Chapter 14 pt 2
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 02/26/16
Chapter 14 Part 2 Solution process 1. ΔHsolute>0 ΔHsolvent>0 ΔHmix<0 Heat of Hydration ionic compounds, water overcome, energy water and ions attractive forces, ions=lattice E ΔHsolute= ΔHlatticeE attractive fprces in water, H bonds ion and water= ion dipole ΔHhydration=heat released/mol gas=ΔHsolvent+ΔHmix Ion Dipole ionshydrated, formation is exothermic Heat of Solution, Ionic ΔHsolution=ΔHsolute+ΔHsolvent+ΔHmix ΔHsolution= ΔHlatticeE+ΔHsolvent+ΔHmix ΔHsolution= ΔHlatticeE+ΔHhydration ΔH solution and ΔHhydration exothermic, lattice E sign ΔHsolution tells ΔHhydration ΔHhydration<ΔHlattice, ΔHsolution endothermic ΔHhydration>ΔHlattice, ΔH solution exothermic example 1: 21500=ΔH583= 604 kJ/mol=ΔHlattice Solution Equilibrium no solute, dissolution dissolve solute, solute reform solute rate dissolution >> rate of deposition, solute dissolves rate dissolution= deposition, aturated no more will dissolve Solubility Limit dynamic equilibrium saturated no more will dissolve depends on pressure and temperature less solute than saturated, or unsaturated more will dissolve at a higher temperature more solute than saturated, can become supersaturated More dissolve if you heat the substance then cool it supersaturated substances are unstable and loose saturation when disturbed : example: soda Temperature dependence of solubility in water raise temperature, solubility in 100g of water solids solubility increases as temperature increases ΔHsolution is endothermic solubility curves can be predicted: solubility vs. Temperature ΔGsoln=ΔHsolnTΔSsoln (++) 1 Purification by crystallization remove impurities dissolve solid in hot solvent until saturated as solution cools, the impurities will be left in the solution, and the purity will crystallize out examples: KNO3 106 g H2O 60 degrees celsius to 0 degrees celsius 139 g left in solution rest precipitate example 2: look at graph 50 g KNO3 100g H2O 34 degrees celsius: aturated 50 g KNO3 100g H2O 50 degrees celsius: nsaturated 50 g HNO3 50g H2O 50 degrees celsius:supersaturated Temperature dependence solubility of gas in water gas solubility decreases, increase in solubility when gas is reacting: carbon dioxide all gases solubility decreases as temperature increases ΔHsolution exothermic, cannot overcome solutesolute interactions ΔGmix=ΔHmixTΔSmix Pressure dependence solubility of gas in water larger partical pressure gas with liquid, more soluble of gas in liquid Henry’s Law solubility gas is portional to partial pressure Sgas=KhPgas example 3:0.1214= CO2 0.1214(3.14x10^2)=3.5 atm example 4:7.6 torr=NH3 0.1L 58(0.01)=5.8x10^1 M M=5.8x10^10 M/L (.10L)17.04g=0.99g NH3 Concentrations Molarity=mol of solute/Lsolution, molaity=mol solute/kgsolvent Mol fraction molsolute/total mol in solution=Xa ntotal=1 Mixtures homogeneous solutions, suspensionsheterogenous do not separate colloidslight will scatter Soaps colloid suspensions, missile particles 2
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'