CHEM 142 Lecture Notes - Lecture 5: Lewis Structure, Nail Polish, Ck-12 Foundation

• School: Emory University
• Department: Chemistry
• Course: CHEM 142
• Professor: Mulford Douglas

Document Summary

In the last worksheet, we spent a fair amount of time working with three intermolecular forces (dipole-dipole, dispersion forces, and hydrogen bonding). We used this knowledge to predict relative boiling points for pairs of compounds like ethanol and dimethyl ether. Now, we want to explore in detail what it means for a substance to boil and discuss other physical properties that relate to the type and strength of intermolecular forces present in a substance. How would that compare with the melting point of solid water? (hint: what interactions are involved for water and for sodium chloride?) Ion ion interactions are very strong, much stronger than hydrogen bonding or dipole dipole interactions which involve only partial charges. Due to this ionic compounds will have very high melting points: we experience ice melting on the macroscopic level on a fairly regular basis. Draw a picture below showing the process of solid water melting on the molecular level.