On Wednesday February 15, 2012, two of the main topics we discussed were Coulomb’s Law exam topic reviews and naming compounds.

Coulomb’s Law is the idea that as ion charge increases, the attractive force increase and as the distance between ions increases, the attractive force decreases.

Force=K(charge q1)(charge q2) / distance

NaCl, Na+ and Cl- -> melting point 804 degrees Celsius

MgO, Mg+ and O2- -> melting point 2800 degrees Celsius

The attraction between the particles is greater which means higher melting point.

Acetaminophen: This is an active ingredient of Tylenol, C₈H₉NO₂                      

Caffeine: This is located in drinks such as soda like the Pepsi in my refrigerator, C₈H₁₂N₄O₃

Fructose: This is a sugar found in fruits, such as the pineapple in my refrigerator, C₆H₁₂O₆

Isopropanol: This is the main component in rubbing alcohol, C₃H₈O

Methylpyrazine: Is used as flavor in bakery goods and chocolate products from Valentine’s Day, C₅H₆N₂

Ionic compounds tend to have higher melting points because the greater the force of attraction between the particles or as the ion charges increase means it will take more force for the change of state.