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You'll find Sec 11.2 (Intermolecular Forces) and Secs 13.1 (The Solution Process) and 13.3 (Factors Affecting Solubility) to be especially helpful for this lab.
For part A, Solubility of Alcohols in Water and Hexane, you are systematically investigating how an increase in nonpolar character of a solute affects solubility in polar and nonpolar solvents. Note that 'like dissolves like' - polar solutes tend to be soluble in polar solvents, and nonpolar solutes in nonpolar solvents. Molecules can, however, have polar and nonpolar constituents, and you are to explain how these affect solubility in terms of the three interactions (solvent/solvent, solute/solute, and solvent/solute.) Discuss these interactions in terms of the predominant intermolecular force (London dispersion, dipole-dipole.)
For part B, note that glass is primarily Si-O2 - this is a polar substance. Tygon is primarily Si-CH3, which is nonpolar. Think about the effect of the polarity of the glass and tygon on how the liquids move within the tubes.
For part C: copper (II) sulfate is an ionic compound, and iodine a molecular one. Think about the nature of the intermolecular force (the ion-dipole force) which makes copper (II) sulfate dissolve in water - this would have to be a pretty powerful force to overcome the ionic bonds in the copper (II) sulfate, wouldn't it?
The report:
Begin with a brief intro (i.e., state the purpose of the experiment and state generally how the experiment will be done.)
A procedure section is not neccessary here.
Results
For the data/results section, make separate tables for parts A, B, and C. For example, the table for part A might look like:
| Methanol | Ethanol | Propanol | Butanol | Pentanol | |
| H2O | M | M | M | PS
butanol layer increased |
|
| Hexane |
Describe your data/results for the mixing of each substance. Notice that M means miscible (soluble in all proportions), IM means immiscible (did not mix - separated into original layers), and PS means partially soluble. You'll need to keep track of which layer is which before you mix two subtances, and be prepared to state how the layers changed sizes.
Repeat with observation tables for parts B and C. For part B, include millimeter measurements of the heights to which the liquids climbed the tygon tubing and glass. For part C, notice that copper (II) ions in water impart a bluish color to the water.
Discussion
Use tables with row/column headings similar to those in the data/results section. For each case in parts A and C, describe the predominant solvent/solvent, solute/solute, and solvent/solute interactions (in that order) in terms of the appropriate intermolecular force (dipole-dipole, London force, ion-dipole.)
For example, the Table for Part A might look like
| Methanol | Ethanol | Propanol | Butanol | Pentanol | |
| H2O | 1.dipole-dipole
2.dipole-dipole 3.dipole-dipole |
||||
| Hexane | 1.London dispersion
2.Dipole-dipole 3.London dispersion |
Notice that interaction 1 is the solvent/solvent interaction, 2 is the solute/solute, and 3 is the solvent/solute interaction.
For part B, state only the predominant intermolecular force operating between the liquid and the glass or tygon tubing.
Also include a table containing the dipole moments for water, hexane, and the five alcohols as calculated by Spartan.
Write a short summary paragraph which describes how polarity affects the way in which molecules interact in terms of solubility of a given solute in a given solvent.