matarsóda* ;)

http://www.cocaine.org/

To obtain crack-cocaine, ordinary cocaine hydrochloride is concentrated by heating the drug in a solution of baking soda until the water evaporates. This type of base-cocaine makes a cracking sound when heated; hence the name “crack”. Base-cocaine vaporises at a low temperature, so it can be easily inhaled via a heated pipe.

http://www.erowid.org/chemicals/cocaine/cocaine.shtml

“ The term ”Crack“ is alternately used to refer to street quality freebase cocaine, or to refer to the product of a particular manufacturing process which uses sodium bicarbonate rather than a flammable solvent. Powdered cocaine is generally insufflated (snorted) and crack / freebase cocaine is generally smoked. Smoking freebase cocaine causes a strong, short-lived peak of about 3-5 minutes, while snorting cocaine provides a lower high with major effects lasting closer to 15 - 30 minutes.”