# Unit 3: Intermolecular Forces and Properties

## 3.13 Beer-Lambert Law

The Beer-Lambert law relates the absorption of light by a solution to three variables according to the equation We can determine the concentration (molarity) of a sample by looking at the absorbance Factors Affecting Calculations Dilution (left water)→ measured...

## 3.12 Photoelectric Effect

Photoelectric Effect: the wavelength of the photon is related to the frequency of the radiation When a photon is absorbed or emitted by an atom or molecule, energy is increased or decreased by an amount equal to the energy of the photon Planck's Constant Planck’s...

## 3.11 Spectroscopy and the Electromagnetic Spectrum

Spectroscopy Applying different types of radiation to atoms and molecules can give info Energy lvls: UV > Visible > Infrared > Microwave Ultraviolet/visible radiation: transitions electrons from one energy lvl to another (higher) one Gives info about atomic...

## 3.10 Solubility

“Like dissolves Like” (don’t say it in exam) → Water dissolves polar molecules (have dipole moment) and does not dissolve nonpolar molecules          ○ polar–polar and nonpolar–nonpolar → are more attracted to each other than themselves → the heat of solution is...

## 3.9 Separation of Solubility and Mixtures Chromatography

Filtration Filtration can be used to separate the insoluble components of a heterogeneous mixture based on differences in particle size but NOT the components of two miscible liquids                                                                                     ...

## 3.8 Representation of Solution

Molarity (M): A.K.A Concentration Ex: A solution that is 1.0 molar (written as 1.0 M) contains 1.0 mole of solute per liter of solution. Note: brackets around something it means the “molarity of what is inside” Dilution: water is added to achieve the molarity desired...

## 3.7 Solutions and Mixtures

Water: The Universal Solvent Water is a very versatile solvent because polar molecules are attracted to other polar molecules + its molecules form HB (adhesive)         ○ (+) and (-) attraction Why are ionic compounds soluble in water?         ○ When ionic compounds...

## 3.6 Deviation from Ideal Gas Behavior

For real gases, the deviation from ideal behavior and predicted pressure is bcuz the particles of real gases have volume and intermolecular forces → PV does not equal nRT The gas which gas deviates the most from ideal behavior will be the one with the strongest IMF...

## 3.5 the Kinetic Molecular Theory of Gases

Gases consist of particles (atoms or molecules) that are in constant random motions Gas particles are constantly colliding with each other and the walls of their container There are no interactive forces (attraction or repulsion) between the particles of a gas...

## 3.4 Ideal Gas Laws

A Gas (Review) Uniformly fills any container (have variable volume) Mixes spontaneously and completely with any other gas Exerts pressure on its surroundings Pressure Is equal to force/unit area Pressure equals the number of collisions with the particles and its...

## 3.3 Solids, Liquids, and Gas

The Three States of Matter Gas: molecules/atoms have enough energy to move freely ○ Particles so far apart from each other that intermolecular forces not considered ○ Indefinite shape and volume Liquid: strong intermolecular forces and molecular motions ○ Particles...