19. PH is the degree of acidity or alkalinity of a solution. It is related to the concentration of Hydrogen ion (H+) in the solution. i.e the pH is: pH = 'log10 [H+]: "It is a measure of the activity of hydrogen ions (H+) in a solution. ("PH", 2006).
These tests may be used to monitor the progress of kidney dysfunction, to evaluate kidney function prior to some procedures, such as a CT (computed tomography) scan, to calculate a creatinine clearance: measures how effectively the kidneys are filtering small molecules like creatinine out of the blood. Urine creatinine may also be used with a variety of other urine tests as a sort of correction factor. Serum creatinine is used to calculate the estimated glomerular filtration rate (EGFR), which is used as a screening test to look for evidence of kidney damage. ("Creatinine")
21. The chemical formula of cocaine is C17H21NO4 , and Crack is [C16H20NO4 ] is very similar indeed. They both contain same number of carbon atoms and oxygen but while regular cocaine has a dissociated NH+ and Cl-, Crack cocaine is an amine because it contains a nitrogen atom bonded to three carbons.
22. Cocaine Hydrochloride can be converted into crack by dissolving powder cocaine is dissolved in a mixture of water and sodium bicarbonate (baking soda). Baking soda with chemical formula NaHCO3 is now most often used as a base rather than ammonia for reasons of lowered stench and toxicity. The mixture is boiled to separate out the solid, and then it's cooled. The solid is then dried and cut up into small nuggets, or "rocks." (Watson, n.a). The reaction is proceeds as follows: