Quimica

OBJECTIVES
Learn about theoretical boiling point
Investigate different ways to solve concentration problems
Find out if it could be changes in the results

INTRODUCTION
Colligative propertiesare properties of solutions that depend on the number of molecules in a given volume of solvent and not on the properties/identity (e.g. size or mass) of the molecules.[1] Colligative propertiesinclude: relative lowering of vapor pressure; elevation of boiling point; depression of freezing point and osmotic pressure. Measurements of these properties for a dilute aqueous solution of a non-ionizedsolute such as urea or glucose can lead to accurate determinations of relative molecular masses. Alternatively, measurements for ionized solutes can lead to an estimation of the percentage ofionization taking place.
Colligative properties are properties of a solution that depend mainly on the relative numbers of particles of solvent and solute molecules and not on the detailed properties of themolecules themselves. You could almost refer to these as statistical properties because they can be understood solely on the basis of counting the relative numbers of particles in a solution. We willderive equations for the colligative properties of ideal solutions. The equations we derive will be valid for ideal solutions and for real solutions in the limit of small concentrations. Nonidealsolutions require that corrections be made to these ideal equations because in nonideal solutions the details of intermolecular interactions become important.
We will discuss four colligative properties:1. Vapor pressure depression
2. Boiling point elevation
3. Melting point depression
4. Osmotic pressure
In all of the following discussion we will denote the solvent as component #1 and thesolute as component #2. For example, the mole fraction of component 1 will be symbolized by X1, and so on.
Vapor pressure depression is relatively easy to understand on the basis of a physical...