IM Forces Section 10.1. States of Matter Forces Between Particles in Solids and Liquids Ionic compounds –Attractive forces between oppositely charged.

Slides:



Advertisements
Similar presentations
Chapter 11 Liquids and Intermolecular Forces
Advertisements

Solutions and Colligative Properties
Physical Properties of Solutions Chapter 12 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
SOLUTIONS Chapter 15. What are solutions?  Homogeneous mixtures containing two or more substances called the solute and the solvent  Solute- is the.
Intermolecular Forces and
Unit 2: Liquids and solids, solubility, equilibrium Will Barkalow and Price Ryan.
Chapter 11 Intermolecular Forces. A phase is a homogeneous part of the system in contact with other parts of the system but separated from them by a well-defined.
CHM 112 M. Prushan Chapter 11 Solutions and Their Properties.
Properties of Solutions
Physical Properties of Solutions
To go with Chapter 13: Silberberg Principles of General Chemistry
Intermolecular Forces Attraction forces that exist between molecules There are four types of intermolecular forces. Strongest to Weakest.
Solutions... the components of a mixture are uniformly intermingled (the mixture is homogeneous).
Physical Properties of Solutions.  Homogeneous mixtures: ◦ Solutions – ions or molecules (small particles) ◦ Colloids – larger particles but still uniform.
Metallic Solids Metals are not covalently bonded, but the attractions between atoms are too strong to be van der Waals forces In metals valence electrons.
IM Forces Section States of Matter Forces Between Particles in Solids and Liquids Ionic compounds –Attractive forces between oppositely charged.
CH 11: Properties of Solutions
Chapter 11 Liquids and Intermolecular Forces
Intermolecular Forces Why do some solids dissolve in water but others do not? Why are some substances gases at room temperature, but others are liquid.
Chapter 11 Liquids and Intermolecular Forces
© 2009, Prentice-Hall, Inc. How Does a Solution Form If an ionic salt is soluble in water, it is because the ion- dipole interactions are strong enough.
Energy and phases. All matter can undergo changes in its state. These changes have to do with the amount of energy in the particles of matter.
Intermolecular Forces and Liquids and Solids Chapter 11.
Liquids & Solids.
Properties of Solutions. Solutions Solutions are homogeneous mixtures of two or more pure substances. In a solution, the solute is dispersed uniformly.
Unit 2 Liquids, solids, solubility, and equilibrium.
Solutions –Review of Solutions –Intermolecular Forces and Solutions (or Like Dissolves Like) –Factors in Solubility –Types of Solutions –Factors in Rate.
Liquids and Solids and Intermolecular Forces Chapter 11.
Intermolecular Forces, Liquids, and Solids
Bond types Bond type electron Electronegativity difference IonicDonate/take>1.7 Polar covalent Share Nonpolar covalent Share
Solutions Chapter 13 Properties of Solutions. Solutions Solutions are _______________ mixtures of two or more pure substances. In a solution, the _______________.
Chapter 13 Properties of Solutions. Solutions Solutions are homogeneous mixtures of two or more pure substances. In a solution, the solute is dispersed.
Physical Properties of Solutions Chapter 12. A solution is a homogenous mixture of 2 or more substances The solute is(are) the substance(s) present in.
Chapter 9 Solution Concentrations and Colligative Properties.
Colligative Properties. _______________ – physical properties of solutions that are affected only by the number of particles NOT the identity of the solute.
Classification of Matter Solutions are homogeneous mixtures.
Chapter 10 Liquids and Solids. Chapter 10 Table of Contents Copyright © Cengage Learning. All rights reserved Intermolecular Forces 10.2 The Liquid.
Intermolecular Forces and Liquids and Solids Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. บทที่ 2b.
The boiling point of a substance is a measure of the amount of energy needed to:  increase the speed of the molecules in the liquid phase to that of.
Solutions Homogeneous mixtures containing two or more substances. –Solvent- The substance that dissolves –Solute- The substance being dissolved.
States of Matter and Intermolecular Forces Chapter States and State Changes.
Chapter 13: Properties of Solutions Sam White Pd. 2.
© 2015 Pearson Education, Inc. Chapter 11 Liquids and Intermolecular Forces James F. Kirby Quinnipiac University Hamden, CT Lecture Presentation.
Chap 10 Liquids & Solids. Key terms Molecules – atoms joined by covalent bonds (molecular compounds) Condensed states – solid and liquid Intramolecular.
Chapter #12 States of Matter Inter-particle Forces.
Liquids Forces Between Liquid Molecules and their Effect on the Properties of Liquids.
Solutions in Chemistry. You are responsible for taking notes from this powerpoint! In class you may work with your group to do calculations and answer.
Physical Properties of Solutions Chapter 12. Objectives 1.0 Define key terms and concepts. 1.8 Explain how a solute and solvent interact to make a solution.
Intermolecular Forces and Liquids and Solids Chapter 11 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Chapter 11 Intermolecular Forces and Liquids and Solids.
Solutions Mixtures: - Heterogenous Mixture: substances that make up the mixture are not spread uniformly throughout the mixture. - Homogenous Mixture:
Name __________________________ Block_____ Chapter 17 Solutions and Molarity Some Definitions A solution is a homogeneous mixture of 2 or more substances.
INTERMOLECULAR FORCES
Solutions. Occur in all phases u The solvent does the dissolving. u The solute is dissolved. u We will focus on aqueous solutions.
 Why does water melt at 0 degrees Celsius and vaporize at 100 degrees Celsius?  e_viewer.php?mid=120.
Chapter 13 Properties of Solutions
Solutions.
Mr. Kinton Honors Chemistry
Liquids Forces Between Liquid Molecules and their Effect on the Properties of Liquids.
Liquids Forces Between Liquid Molecules and their Effect on the Properties of Liquids.
Intermolecular Forces
Chapter 11 – Liquid and Intermolecular Forces
Properties of Solutions
Chapter 13 Properties of Solutions
Chapter 11 Liquids and Intermolecular Forces
Aim: What are intermolecular forces and Intramolecular forces?
Solutions Chapter 15 Chapter 16.
Chapter 11 Liquids, solids, and intermolecular forces
Intramolecular and Intermolecular Forces
Presentation transcript:

IM Forces Section 10.1

States of Matter

Forces Between Particles in Solids and Liquids Ionic compounds –Attractive forces between oppositely charged ions hold ionic compounds together. –Ionic bonds are the strongest interparticle force. –Smaller the ion and the larger the charge on the ion the stronger the attractive forces among the ions

Ionic Bonding

Forces Between Particles in Solids and Liquids Forces between molecular compounds –Intermolecular (IM) forces between molecules attract molecules to each other in the liquid and solid state. IM forces are very weak as compared to ionic or covalent bonds

IM Forces Three types of IM Forces 1.Dipole-dipole force 2.Hydrogen “bonding” 3.London dispersion forces See pages

Interparticle Forces and Physical Properties The stronger the attractive forces between particles in a liquid or solid, the –Higher the: Melting point Boiling point Surface tension Viscosity –Lower the: Vapor pressure

IM Forces Dipole-dipole forces –Attractive forces between oppositely charged dipoles. –Dipole-dipole forces are found between polar compounds. The more polar the compound the stronger the dipole-dipole force.

IM Forces Hydrogen “bonds” –Attractive force between a  + H bonded to an O, N, or F and a  - O, N, or F generally on another molecule. Really a relatively strong dipole-dipole force –Hydrogen bonding is the strongest of the IM forces. –H bonding is very important in water and in many biological molecules.

Hydrogen “bond” is a weak attractive force between a  + hydrogen and a  -  O, N, or F in a second polar bond

London Dispersion Forces London Dispersion force –Very weak and short-lasting attractive forces between temporary dipoles See figure 10.5 –Weakest of the IM forces

London Dispersion Forces London Dispersion forces –Found between all molecules in liquid/solid state. Of greatest significance in nonpolar molecules as it’s the only IM force between nonpolar molecules –The larger the molecule the stronger the dipersion forces.

Dispersion Forces Occur between every compound and arise from the net attractive forces amount molecules which is produced from induced charge imbalances The magnitude of the Dispersion Forces is dependent upon how easily it is to distort the electron cloud. The larger the molecule the greater it’s Dispersion Forces are.

Dispersion Forces and Molecular Shape Elongated molecules have higher dispersion forces than compact molecules Ringed structures have higher dispersion forces than straight chain molecules. –Consider: Hexane Cyclohexane 2,2 – dimethyl butane

Interparticle Forces Weakest to Strongest: Intermolecular forces – all relatively weak London dispersion forces Dipole-dipole force Hydrogen Bonding Ionic bond - BY FAR THE Strongest: - not an IM Force

Properties of Liquids Freezing and boiling point Surface tension Capillary action Viscosity  Which are directly related to the strength of the IM forces present between molecules?

Change of State Normal Freezing/Melting point –temperature at which the liquid and solid state co-exist at 1 atm pressure Normal boiling point –temperature at which the liquid and gaseous state co-exist at 1 atm pressure Predict the relative BP of: –Methane, acetone, methanol, ethanol, NaCl

Surface Tension Surface tension –Resistance of a liquid to increase its surface area –Measure of the energy needed to break the IM forces at the surface

Capillary Action Capillary action –Spontaneous rising of a liquid in a narrow tube Related terms: –Cohesive forces – attractive forces among like molecules –Adhesive forces – attractive forces among dislike molecules

See Figure 10.7, page 444 Concave meniscusConvex meniscus Adhesion > CohesionCohesion > adhesion

Viscosity Viscosity – resistance of a liquid to flow –Highly viscous liquids are thick (syrupy) –Consider relative viscosity of: Propanol Glycerol

Graphite Layers of ringed carbon structures –Each C is bonded to 3 other C –Each C is sp 2 hybridized

Diamond A diamond is a gigantic molecule, each C atom is bonded to 4 other C atoms Each C is sp 3 hybridized

A phase diagram summarizes the conditions at which a substance exists as a solid, liquid, or gas. Phase Diagram of Water 11.9

CH 11: Properties of Solutions 1.Describing Solutions – concentration units 2.Energetics of solution formation 3.Colligative Properties of solutions BP elevation FP depression Osmotic pressure Vapor Pressure

Terms Solution – homogeneous mixture Solvent – generally the larger component of the solution –Determines the physical state of the solution Solute – generally the smaller component of the solution –Solute is dispersed in the solvent

Solution Composition Concentrated solution – relatively large amount of solute Dilute solution – relatively small amount of solute

Solution Composition Unsaturated solution –solution with less than the maximum amount of solute that will normally dissolve at a given temperature Saturated solution - solution with maximum amount of solute that will normally dissolve at a given temperature

Solution Composition Super-saturated solution - solution with more than the maximum amount of solute that will normally dissolve at a given temperature

Concentration Units Molarity (M) = moles solute/Liters solution Molality (m) = moles solute/kg solvent Mass % = Mass solute/mass solution x100%  Mole fraction (   ) = moles A/total moles

Practice! Start by writing definitions for the concentration units M = m = Mass % = Mole fraction =

Starting with Molarity Solution: –3.75 M H 2 SO 4 solution with a density of 1.23 g/mL Calculate: –Mass % –Molality –mole fraction of H 2 SO 4

Starting with Masses Solution: –A solution is made by combining 66.0 grams of acetone (C 3 H 6 O) with grams of water. –Solution has a density of g/mL Calculate: –Molarity – need volume of solution –Mass % –Molality –Mole fraction of acetone

Starting with Mass % Solution: –35.4 % H 3 PO 4 –Density of 1.20 g/mL Calculate: –Molarity –Molality –Mole fraction of H 3 PO 4

Starting with Molality Solution: –2.50 m HCl solution –Density of 1.15 g/mL Calculate: –Molarity – need _______ –Mass % –Mole fraction of HCl

Solution Formation Formation of a solution involves 3 steps 1.Separate the solute particles expand the solute 2.Separate the solvent particles Expand the solvent 3.Form the solution –Solute and solvent interact

Solution Formation Each step of solution formation involves energy and has a  H.  H 1 = energy needed to separate the solute  H 2 = energy needed to separate the solvent  H 3 = energy released when solution forms

Solution Formation  H solution  H 1 +  H 2 +  H 3 Solutions form when the  H solution is a small value – see page 492

Factors Impacting Solubility Structure – like dissolves like –#38 on page 520

Factors Impacting Solubility Pressure –Pressure has little impact on the solubility of liquids and solids –Pressure has a significant impact on the solubility of gases in a liquid The higher the pressure of gaseous solute above a liquid the higher the concentration of the gas in the solution

Henry’s Law Henry’s Law: C = kP C = Concentration of dissolved gas k = solution specific constant P = partial P of the solute gas above the solution No calculations required. Page 494

Temperature and Solubility Temperature has variable effects on the amount of solid that will dissolve in an aqueous solution! –See figure 11.6 page 496 Solutes do dissolve more rapidly at higher temperatures

Temperature and Solubility The solubility of a gas in water decreases as temperature increases. –See figure 11.7 on page 496 –Thermal pollution – read the story on page 497 when you get a chance

Vapor Pressure of Solutions See Raoult’s Law on page 498 solventsolventP solution =  solvent P 0 solvent

Colligative Properties Colligative properties –properties of a solution that depend upon the amount of dissolved solute, not the identity of the solute. Freezing point depression Boiling point elevation Osmotic Pressure Note: I will be weaving section 11.7 and the van’t Hoff factor (i) into my consideration of these properties and not consider it separately.

Colligative Properties  FP = K f m i  BP = K b m i See page 505 for needed constants

1.Calculating the bp or fp of a solution 2.Calculating the molar mass of a solute from fp or bp data

Osmotic Pressure Osmotic Pressure (  ) is often used to determine the molar mass of large biological molecules –See figure on page 508  = MRTi