1 / 10

Experiment 1:

Experiment 1:. STRUCTURE, INTERMOLECULAR FORCES AND SOLUBILITY. ROLE OF INTER- AND INTRAMOLECULAR FORCES. physical state; solid, liquid & gas solid vs. liquid: (fat vs. oil) liquid vs. gas: (C 2 H 6 O isomers: dimethyl ether vs. ethanol) distillation; difference in BP ( o C)

maris
Download Presentation

Experiment 1:

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Experiment 1: STRUCTURE, INTERMOLECULAR FORCES AND SOLUBILITY

  2. ROLE OF INTER- AND INTRAMOLECULAR FORCES • physical state; solid, liquid & gas • solid vs. liquid: (fat vs. oil) • liquid vs. gas: (C2H6O isomers: dimethyl ether vs. ethanol) • distillation; difference in BP (oC) • extraction; difference in solubility and partition coefficient. • Oil and vinegar dressing • Chromatography: different IMF between analyte and stationary vs. mobile phase • GC of alkanes, TLC, HPLC of analgesics • Biology • secondary structure of proteins: H-bonding between amino acids • DNA and DNA-RNA base pairing: H-bonding between base pairs

  3. INTERMOLECULAR FORCES • London Dispersion Forces: weak attractive forces caused by instantaneous dipoles in molecules. • Dipole-Dipole Forces: Electrostatic attraction between polar molecules. • Ion-Dipole Forces: Electrostatic attraction between an ion and a polar solvent. • Hydrogen Bonding: (2-3 kcals/mole) Electrostatic attraction between the very electropositive H of -O-H and -N-H bonds withthe negative end of other dipoles, especially with oxygen and nitrogen atoms.

  4. DIPOLE - DIPOLE FORCES: • Dipole momentm: Electrostatic attraction between polar molecules. • measure of the unevenness of electron density in a bond or molecule. • depends on both electronegativityof atoms and on molecular geometry.

  5. HYDROGEN BONDING

  6. GOALS OF LAB • Introduction to drawing structures. • Introduction to inter- and intra-molecular forces between organic molecules. • Through solubility testing, discover relationship between structure, intermolecular forces and solubility.

  7. EXPERIMENTAL OUTLINE • A: Test solubility of compounds in hexane and water. • B: Test solubility of organic liquids in water. • C: Test solubility of alcohols in hexane and water. • D: Test solubility of organic solids in diethyl ether, water, acidic and basic solutions.

  8. Table of Common Organic Solvents

  9. SAFETY CONCERNS • All solvents used in today’s lab are volatile. Wear safety goggles at all times, and use fume hoods.

  10. WASTE DISPOSAL • All waste from this experiment goes into the bottle marked: “Solubility Waste (IMF)”.

More Related