tetraethyl lead

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tetraethyl lead

(tĕt'rəĕth`əl), (C2H5)4Pb, viscous, colorless, poisonous liquid. It is an organometallic compound prepared by reacting ethyl chloride with a sodium-lead alloy. When added to gasoline, it improves the combustion characteristics (see octane numberoctane number,
figure of merit representing the resistance of gasoline to premature detonation when exposed to heat and pressure in the combustion chamber of an internal-combustion engine.
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). When tetraethyl lead burns in an engine, lead oxide is formed. Ethylene dibromide is usually also added to the gasoline; on burning, the resulting mixture forms products that react with the lead oxide to form lead bromide, a volatile compound that escapes from the engine with other exhausted products. Because the lead bromide is poisonous, lead-free gasolines are required in the United States. An additional reason for lead-free gas is that the lead in the exhaust pipe would poison the catalytic converter that is standard equipment for U.S. cars. Catalytic converters which serve to oxidize unburned hydrocarbons, carbon monoxide, and nitrogen oxides contain platinum group metals that are inactivated by lead.

tetraethyl lead

a colourless oily insoluble liquid used in petrol to prevent knocking. Formula: Pb(C2H5)4
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(t) Chemicals for which more than 25% of sites had modeled or monitored levels that exceeded the associated health reference level in the United States: acetaldehyde, acrolein, arsenic, benzene, beryllium, carbon disulfide, carbon tetrachloride, chloroform, ethylene oxide, formaldehyde, hydrogen sulfide, methyl ethyl ketone, methyl isocyanate, methyl methacrylate, nitrobenzene, prerchloroethylene, phenol, phthalic anhydride, styrene tetramethyl lead, toluene diisocvanate, and vinyl chloride.
binapacryl; DNOC and its salts; ethylene dichloride; ethylene oxide; monocrotophos; parathion; toxaphene and dustable powder formulations containing a combination of benomyl at or above 7 per cent, carbofuran at or above 10% and thiram at or above 15%; actinolite asbestos; anthophyllite asbestos; amosite asbestos; tremolite asbestos; tetraethyl lead and tetramethyl lead; parathion; and chrysotile asbestos.