Strong acid administered intravenously

The most important type of mixed solution is a buffer, a solution in which the pH resists change when small amounts of strong acids or bases are added. Buffers are used to calibrate pH meters, to culture bacteria, and to control the pH of solutions in which chemical reactions are taking place. They are also administered intravenously to hospital patients. Human blood plasma is buffered to pH = 7.4 the ocean is buffered to about pH = 8.4 by a complex buffering process that depends on the presence of hydrogen carbonates and silicates. A buffer consists of an aqueous solution of a weak acid and its conjugate base supplied as a salt, or a weak base and its conjugate acid supplied as a salt. Examples are a solution of acetic acid and sodium acetate and a solution of ammonia and ammonium chloride. 

Heroin is a diester of morphine (3,6-diacetil morphine or DAM) obtained from the acetylation of both hydroxylic groups. It is a white, crystalline powder, with a bitter taste. It is unstable in air and light and typically produces an odor of acetic acid. Heroin, similarly to morphine, can be combined with acids producing water soluble salts, such as heroin hydrochloride. Similarly to morphine, it possesses narcotic and analgesic activity, but heroin causes strong addiction and intoxication. It is administered through inhalation, parenteral, subcutaneous, and above all intravenous. 

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