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Some Definitions. A solution is a _______________ mixture of 2 or more substances in a single phase. One constituent is usually regarded as the SOLVENT and the others as SOLUTES. Parts of a Solution. SOLUTE – the part of a solution that is being dissolved (usually the lesser amount) - PowerPoint PPT Presentation

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Solutions

Some DefinitionsA solution is a _______________ mixture of 2 or more substances in a single phase. One constituent is usually regarded as the SOLVENT and the others as SOLUTES.

#Page #Parts of a SolutionSOLUTE the part of a solution that is being dissolved (usually the lesser amount)SOLVENT the part of a solution that dissolves the solute (usually the greater amount)Solute + Solvent = SolutionSoluteSolventExamplesolidsolidsolidliquidgassolidliquidliquidgasliquidgasgas#DefinitionsSolutions can be classified as saturated or unsaturated.A saturated solution contains the maximum quantity of solute that dissolves at that temperature.An unsaturated solution contains less than the maximum amount of solute that can dissolve at a particular temperature

#DefinitionsSUPERSATURATED SOLUTIONS contain more solute than is possible to be dissolvedSupersaturated solutions are unstable. The supersaturation is only temporary, and usually accomplished in one of two ways:Warm the solvent so that it will dissolve more, then cool the solution Evaporate some of the solvent carefully so that the solute does not solidify and come out of solution.

# SupersaturatedSodium AcetateOne application of a supersaturated solution is the sodium acetate heat pack.

#HomeworkRead section 8.5Pages 392-386

Page 395 #1-3Page 397 #1-4,6#IONIC COMPOUNDSCompounds in Aqueous SolutionMany reactions involve ionic compounds, especially reactions in water aqueous solutions.

KMnO4 in water

K+(aq) + MnO4-(aq)

#To play the movies and simulations included, view the presentation in Slide Show Mode.

Page #How do we know ions are present in aqueous solutions?The solutions _________________________They are called ELECTROLYTESHCl, MgCl2, and NaCl are strong electrolytes. They dissociate completely (or nearly so) into ions.

Aqueous Solutions#Aqueous SolutionsSome compounds dissolve in water but do not conduct electricity. They are called nonelectrolytes.

Examples include:sugarethanolethylene glycol#Laboratory Concentration of SolutionsThe amount of solute in a solution is given by its concentration.Molarity(C)=moles solute(n)litres of solution(V)

Units for molarity are mol/L also written as mol L-1 and M#PROBLEM: Dissolve 5.00g of NiCl26 H2O in enough water to make 250 mL of solution. Calculate the molar concentration.Step 1: Calculate moles of NiCl26H2O

Step 2: Calculate Molarity[NiCl26 H2O ] = 0.0841 M

#Try this problem25.0 g of NaCl is dissolved in 5000.0 mL of water. Find the molar concentration of the resulting solution.

C = n/V

25.0 g NaCl 58.5 g/mol NaCl= 0.427 mol NaClC = n/V0.427 mol NaCl 5.000 L= 0.0854 M NaClConvert volume to L mlL divide by 1000Convert mass of solute to moles5000.0 mL = 5.000L#Step 1: Change mL to L.250 mL = 0.250 LStep 2: Calculate moles using n = CV.Moles = (0.0500 mol/L) (0.250 L) = 0.0125 molesStep 3: Convert moles to mass.(0.0125 mol)(90.00 g/mol) = 1.13 gUSING MOLARITYMoles(n) = CVWhat mass of oxalic acid, H2C2O4, isrequired to make 250. mL of a 0.0500 Msolution?#Learning CheckHow many grams of NaOH are required to prepare 400. mL of 3.0 M NaOH solution?

1)12 g2)48 g3) 300 g

#Using Molarity Cont.What volume of solution would contain 42.6g of sucrose with concentration of 0.525M?V = n/CConvert mass to moles Moles = 42.6g / 342 g/mol = 0.1246 molesV = n/CV= 0.1246 mol/0.525M = 0.237L#PracticePage 400 #1-4#