[PDF] [PDF] Chapter 11 - Welcome to webgccazedu

[PDF] Solutions - UTC

Normality = equivalents of solute/ L of solution Notice that in the above problem In some problems value of i maybe given and not be an integer because 

[PDF] IMPORTANT CHEMICAL CONCEPTS: SOLUTIONS - Cal State LA

Normality (N) = #equivalents solute/#liters of solution Normality must be specified with respect to a definite reaction a For acid-base reactions, 1 equivalent = 1 

[PDF] DRPUSALKAR PROBLEMS BASED ON - VG Vaze College

the solute to one 100 parts by volume of the solution 11)Normality: It is defined as the number of gram equivalents of the solute dissolved in one dm 3

[PDF] Chemistry 1210 Normality Problems - KPU WordPress

Chemistry 1210 Normality/Redox Problems 1) A sample of iron ore weighing 0 2792 grams was dissolved in dilute acid solution, and all of the iron was 

[PDF] Practice Problems: Solutions (Answer Key)

6 avr 2016 · The density of the solution is 0 982 g/mL and the density of water is 1 00 g/mL Molarity: 15 8 M NH 3 , molality: 22 1 molal NH 3

[PDF] Stoichiometric calculations

Normality • A one-normal solution, 1N, contains one equivalent of species per liter • An equivalent 'represents the mass of material providing Avogadro's 

Solutions to normality primer

Problems Acid- BaseTitrations 1 Convert the following to equivalents a 0 12 mol H2SO4 for H2SO4 with 2 acidic protons (H+), 1 mol = 2 eq 0 12 mol x (2 eq/1  

[PDF] Molarity, Molality and Normailty

Chapter 12: Molarity, Molality, Normality, and Mass Percent Worksheet II Date _____/_____/_____ Period _____ Molarity = Moles of solute / Liters of Solution  

[PDF] Chapter 11 - Welcome to webgccazedu

Solutions – ions or molecules (small particles) – Colloids Also ppm, mole fraction, molality, and Normality Molarity = moles solute / liter solution = mol/L

[PDF] normering examen economie havo 2016

[PDF] northrop grumman das

[PDF] northrop grumman f 35 cni

[PDF] northstar listening and speaking pdf

[PDF] notation scientifique exercices corrigés 4eme

[PDF] notation scientifique seconde exercice corrigé

[PDF] note names in the bass sheet answers

[PDF] note values worksheet

[PDF] notes of c language

[PDF] notes of c language for bca

[PDF] notes of c language pdf

[PDF] notes of c language pdf download

[PDF] notes of c language pdf in hindi

[PDF] notes of chemistry chapter 2

[PDF] nothing bundt cakes

Chapter 11Chapter 11Chapter 11Chapter 11

11

Solutions and

Their Properties

Solutions

•Homogeneous mixtures: -Solutions - ions or molecules (small particles) -Colloids - larger particles but still uniform (milk, fog)

The Solution Process

•During dissolution, some forces are broken and new forces are created 33

The Solution Process

•Solvent-solvent interactions •Solute-solute interactions •Solvent-solute interactions ΔΔΔΔHsoln= ΔΔΔΔH1+ ΔΔΔΔH2+ ΔΔΔΔH3 44

Figure 12.2

The Solution Process

•Generally,

•if the solute is more strongly attracted to the solvent attraction (than to itself -weak IMF), then dissolution is favorable; exothermic (

ΔΔΔΔHsoln< 0)

•if the solute is more strongly attracted to itself (than to the solvent - strong IMF), then dissolution is not favorable; endothermic (

ΔΔΔΔHsoln> 0)

Hot and Cold Packs

•Hot packs - dissolving solid releases heat -CaCl2(s)ΔΔΔΔHsoln= -81.3 kJ/mol -MgSO

4(s)ΔΔΔΔHsoln= -91.2 kJ/mol

•Cold packs - dissolving solid absorbs heat -NH4NO3(s) ΔΔΔΔHsoln= +25.7 kJ/mol

Ways of Expressing Concentration

•Variety of units -Most commonly used is M (molarity) -Also ppm, mole fraction, molality, and Normality •Qualitative terms relating to solubility -insoluble, slightly soluble, soluble, very soluble - <0.1 g/100g >2 g/100 g •Other comparative terms: -dilute, concentrated (solids in liquids) -miscible, immiscible, partially miscible (liquids in liquids) 77

Concentration Units

•Molarity -Molarity= moles solute / liter solution = mol/L -Depends on temperature; density of liquids changes with temperature (d

H2Oat 20oC =

0.9982 g/cm

3) -Molarity: -Ex: 5.0 g NaCl in water that gives a volume of 251mL -Ans: 0.34 M NaCl •Mole fraction (X): -Mole Fraction= mole A / (mole A + mole B) -Ex: 5.0 g NaCl in 251 mL water -Ans: 0.0061 NaCl; 0.994 water 88

Concentration Units

•Mass Percent -Mass Percent= (mass of solute / mass of solution) x 100% -Ex: 5.0 g of NaCl in 251 mL water -Ans: 2.0 % NaCl •Molality -molality= moles solute / kilograms solvent = mol/kg -Independent of temperature because masses do not change with temperature -Ex: 5.0 g NaCl in 251 mL water -Ans: 0.34 m NaCl

Types of Solutions

•Unsaturated solution: contains less solute than it has the capacity to dissolve

Saturated solution: contains the maximum amount

of solute that will dissolve in a given solvent at a specific temperature Supersaturated solution: contains more solute than is present in a saturated solution

Crystallization: process in which a dissolved

solute comes out of solution and forms crystals

Supersaturated Solution

Supersaturated Solution

Acetate

Solid Solubility and Temperature

•Solubility of ionic compounds in water generally increases with higher water temps

Figure 11.6

Effect of Temperature on Solubility

•The solubility of gases in water decreases with increasing temperature. Why? •Solubility goes to 0 at boiling point of water. 1414

Effect of Pressure on Solubility

•Strong effect only for gasesdissolved in liquids. •What happens to the amount of dissolved solute when pressure is increased (2 nd picture)?

1515More dilute solution More concentrated solution

Figure 11.8

Effect of Pressure on Solubility

•Henry"s Law: concentration (solubility) of a gas in a liquid is proportional to the pressure of the gas over the solution •Why does a soft drink fizz when the container is opened? 1616

Molarity to molality

Remember the distinction between molarity (M) and molality (m) M=m=

Moles of soluteMoles of solute

L of solutionkg of solvent

To do these calculations, you must have one extra

piece of information: density What is the molality of a 0.123 MHCl(aq) solution?

The density of the solution is 1.030 g/mL.

What is the molarity of a 3.21

mKOH(aq) solution? (density of solution = 1.163 g/mL)

Colligative Properties

• Colligative properties:depend only on the number of solute particles in solution and not on the nature of the solute particles. The particles may be covalent molecules or ionic compounds. (We"ll only deal with covalent molecules.) • Colligative means "depending on the collection" - Examples: vapor pressure boiling point freezing point osmosis / osmotic pressure 1919

Vapor Pressure Lowering

•Adding a solute to a solvent lowers the P vap •Pvapof a solution < Pvapof a pure solvent 2020

Vapor Pressure Lowering

• Pvapis lowered because fewer surface positions are occupied by solvent molecules and because intermolecular forces in solutions are usually greater than those in the separated substances. Raoult"s Law: partial pressure of a solvent vapor over a solution is the product of the mole fraction of the solvent (X

1) and the vapor pressure of the solvent

(P o1). - P

1= X1Po1

B. P. Elevation/F. P. Depression

•Phase diagrams can be used to see how vapor pressure changes cause changes in boiling and freezing points.

2222

Freezing pure water

Figure 11.12

B. P. Elevation/F. P. Depression

•Lower vapor pressure (red lines)

Freezing solution

Freezing Point Depression

• Changes in freezing point are directly proportional to the number of solute particles • Equations that govern these effects: ΔT f= Kfm ΔT fis the change in normal freezing point - K fis based on the identity of the solvent - m is molality = moles solute/kg solvent • Calculate the freezing point of a solution when 62.345 g of vinyl chloride (CH

2CHCl) is added to 1264 g

cyclohexane.

Boiling Point Elevation

• Changes in boiling point are directly proportional to the number of solute particles • Equations that govern these effects: ΔT b= Kbm ΔT bis the change in normal boiling point - K bis based on the identity of the solvent - m is molality = moles solute/kg solvent • Calculate the boiling point of a solution when 62.345 g of vinyl chloride (CH

2CHCl) is added to 1264 g

cyclohexane. 2525

B.P. Elevation/F.P. Depression

•Kband Kfdepend only on the solventbeing used

Group Work

•Calculate the molar mass of an unknown solute when the freezing point of water is lowered by 7.77°C after 651 g of the solute is dissolved in 2505 g of water.

Osmosis -pickling of cucumbers

Osmotic Pressure

•Osmosis: selective passage of solvent molecules through a porous membrane from a dilute solution to a more concentrated one. -Semipermeable membrane: allows the passage of solvent molecules but blocks the passage of solute molecules.

ΠΠΠ= MRT

3030

Posanim

Reverse Osmosis

•Uses high pressure to force water from a more concentrated solution to a less concentrated one through a semipermeable membrane. The membrane allows water molecules to pass

through but not dissolved ions.quotesdbs_dbs21.pdfusesText_27