In this discussion we will investigate some examples of chemistry in relevant, real-life examples. We will relate these examples to the concepts we have learned in class so far. This discussion will
How is "Crack" Cocaine Different Than Regular Cocaine?
Crack Cocaine is a free base form of cocaine. "Free base" means that it is cocaine in its conjugate base form. Crack can be produced via an acid-base reaction with sodium bicarbonate (NaHCO3):
Cocaine-H+ Cl- (aq) + NaHCO3 (aq) 
⟷ Cocaine (crack) (l)+ H2O(l)+ CO2 (g) + NaCl (aq)
Acid Base Conj. Base Conj. Acid
The above reaction is an equilibrium reaction. The reaction can be manipulated to produce more crack (favor the forward direction) using LeChatelier's principle. By heating the reaction, the CO2 gas will bubble out of the solution. This is due to the decreased solubility of gases at higher temperatures. Because the CO2 is removed from the solution, product concentration is decreased, which drives the reaction in the forward direction.
The free base product (crack) can then be separated from the solution due to its physical properties. Crack is an oily substance, which means it is nonpolar. Because the reaction is done in water, a polar solvent, the crack is not miscible with the aqueous layer, and will separate based on solubility of liquids. Due to the liquid crack having a lower density than water, the crack layer will rise to the top and can be separated.
Once the crack it separated from aqueous layer, it is dried into rocks as a crystalline solid. Crack rocks have the following physical properties: they are brittle white solids, and have a slightly higher density than candle wax. Crack rocks have the following chemical properties: they act as a local anesthetic numbing the tongue or mouth, as well as many physiological effects.
Sources:
Wikipedia article: Crack Cocaine (Links to an external site.)
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