C1 Lesson 1 Kinetic Molecular Force.docx

LESSON 1: KINETIC MOLECULAR MODELS OF LIQUIDS AND SOLIDS KEY WORDS: OBJECTIVE/S: 



Kinetic Molecular Theory

Explain the natre of liquid and solid states using the kinetic molecular theory; and describe the different kinds of intermolecular forces of attractiobn.

Intramolecular forces and Intermolecular forces Ion-dipole force Dipole-dipole force London Dispersion Hydorogen Bond

Described the states of matter in terms of SOLID

Arrangement of Particles

 

Closel packed Orderly

LIQUID 



Kinetic Energy of particles

Particle Motion

Attractive forces between particles

Intermolecular FOrces

GAS

Less closely packed than in a solid Disorderly

 

Very far apart Disorderly



Vibrate and rotate about a fixed position



Slide over each other



Move abot at great speeds



Very low

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Low



High



Very strong



Strong



Very weak

   

Ion-dipole Dipole-dipole London Dispersion Hydrogen Bonding

CHAPTER 1-Compiled by : GUTIERREZ, Bernadeth F.

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CHAPTER 1: INTERMOLECULAR FORCES OF SOLIDS AND LIQUIDS 1.1 The Kinetic Molecular Theory of Solids and Liquids CRITERIA Particle Arrangement

SOLID

LIQUID

***LIQUIDS- due to its particle arrangements, they have: -

Movement

Density Diffusibility Compressibility

Volume and Shape Thermal Expansibility

 Held by very strong forces of attraction  Particle are not free to move  Particle vibrate about in fixed positions Very High Extremely Slow Slightly compressible Has fixed volume and shape Expands slightly when heated

 Held together by strong forces of attraction  Particles are able to slide past one another

-

-

no strong attractive force (that is much as strong as solids) thus, sufficient kinetic energy can overcome their attractive forces. particles that can move at short distance and collide with each other. particles that does not move independently thus, have fixed volume but does not have fixed shape. high diffusion rate and is slightly more compressible than that of solid.

QUESTION TO PONDER: High Slow Slightly compressible (more than solid) Indefinite shape and has fixed volume Expands slightly when heated (more than solid)

How about the Kinetic Molecular Theory of Gas? CRITERIA Particle Arrangement

GAS

Movement

Density ***SOLIDS – due to its particle arrangement, they have: -

strong attractive force thus, the kinetic force is not strong to overcome it. particles that are not free to move thus, vibration is limited fixed and volume slow diffusion rate and can be compressed slightly.

Diffusibility

Compressibility

Volume and Shape

Thermal Expansibility

CHAPTER 1-Compiled by : GUTIERREZ, Bernadeth F.

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1.2 Intermolecular Forces I. Intermolecular vs. Intramolecular

*** Velcro- commonly used as a cloth fastener

Which is stronger intermolecular force or intramolecular force? _______________________________________ _______________________________________ _______________________________________ A. Types of Intramolecular force of attraction Which is ionic and which is covalent?

CO2_______________ CH4_______________

HCl_______________ MgOH_______________

1. Ionic bond: METAL + NON-METAL

__________________________________________ __________________________________________ 2. Covalent Bond: NON-METAL +

NON-METAL; formed between atoms that have similar electronegativity (see attachment of electronegativity table at the last page)

INTERMOLECULAR FORCE

INTRAMOLECULAR FORCE





forces that exist between molecules.

forces that hold atoms together within a molecule.

CHAPTER 1-Compiled by : GUTIERREZ, Bernadeth F.

__________________________________________ __________________________________________

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

Nonpolar covalent bond vs. Polar Covalent bond

NONPOLAR  the difference in electronegativity between bonded atoms is less than 0.5.

POLAR The difference in electronegativity between bonded atoms is between 0.5 and 1.9. chloride POLAR

Which is polar and which is nonpolar? C2H6__________________________ NH3___________________________ CH3OH_________________________ CF4____________________________ PCl5___________________________

b. Metallic Bond- This type of covalent bonding specifically occurs between atoms of metals, in which the valence electrons are free to move through the lattice.

a. Hydrogen directly attached to F, O ,N NONPOLAR a. Monoatomic b. Diatomic

c. Hydrocarbons

b. Lack symmetry  Unidentical elements outside the central element

 The freely moving electrons in metals are responsible for their reflecting property— freely moving electrons oscillate and give off photons of light—and their ability to effectively conduct heat and electricity.

 *** Oscillate- move or swing back and forth at a regular speed

d. Symmetrical Compound



With lone pair

Relative strength of the intramolecular forces

a. Nonpolar covalent bond

Which is stronger? Au or NaCl ______________________________ CH4 or PCl5_______________________________________________ NH3 or H20 ______________________________ CHAPTER 1-Compiled by : GUTIERREZ, Bernadeth F.

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B. Types of Intermolecular forces of attraction 1. Ion-Ion interaction: ION + ION

4. Hydrogen Bond : H+ F, O,N

__________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________

5. London Dispersion forces (Van der Waal)  The more electrons a molecule has, the stronger the London dispersion forces are.

2. Ion-dipole interaction: ION + DIPOLE MOLECULE

__________________________________________ __________________________________________ __________________________________________ Relative strength of intermolecular forces of attraction __________________________________________ __________________________________________ __________________________________________

3. Dipole-dipole interactions: PARTIALLY POSITIVE CHARGE + PARTIALLY NEGATIVE CHARGE

Ion-dipole Hydrogen bond Dipole-dipole London Dispersion ___________________________________________ ___________________________________________ ___________________________________________

The rule of thumb Intermolecular force= force) __________________________________________ __________________________________________ __________________________________________

CHAPTER 1-Compiled by : GUTIERREZ, Bernadeth F.

energy (to break the

 Boiling and melting points of compounds depend on the type and strength of the intermolecular forces present, as tabulated below:

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CHAPTER 1-Compiled by : GUTIERREZ, Bernadeth F.

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