Answer. Gibbs (1990) reports the first commercial use of the other lead alkyls in gasoline occurred in 1960. But there were other effective anti-knock agents. NCERT Solutions; ... TEL i.e. During combustion, tetraethyl lead decomposes to produce lead compounds, which are poisonous. It is an anti-knocking substance is added to petrol to decrease the ignition of petrol vapours. Thus, poisonous lead compound are present in the exhaust of automobiles. It was still considered to be the fuel that would eventually replace petroleum. TEL, tetraethyl lead, acts ... chemistry. Antiknock agent. Which compound is added to petrol to prevent engins from knocking causes air pollution of air - Science - Coal and Petroleum. For years, tetraethyl lead (TEL), an anti-knock agent, has been added to gasoline and aviation fuels. Tetraethyllead (TEL) was first introduced into automotive gasoline as an antiknock agent in 1923 (Gibbs, 1990).It was the lone lead alkyl compound added to automotive gasoline up until the early 1960s. It was far too expensive, so lead tetraethyl was developed to replace it. Anti-knocking agent such as, tetraethyl lead is added to petrol/diesel to make its combustion smoother. Tetraethyl lead and other lead compounds are no longer used in most areas to increase octane rating (still used in aviation and auto-racing). Also see lead free … Dictionary of automotive terms. C. electophile. D. nucleophile. In the 1970s, regions around the world began phasing out lead in motor gasoline. It acts as: A. negative catalyst. Usually added to gasoline to raise its octane value. Medium. B. catalyst. Antiknock agents are the chemical compounds added in small quantities (less than 1 percent) to motor fuels to improve the antiknock ratings of the fuel. TEL, tetraethyl lead, acts as an anti-knocking agent. Iodine was the first anti-knock substance to be used to prevent engine knock. This is seen in a May, 1922 memo from Midgley to Kettering that evaluated a report on alcohol production from the century plant of the Mexican desert. Tetraethyl lead is added to petrol as an antiknocking agent. tetraethyl lead — (TEL) a lead compound used as an additive to increase the octane rating and reduce the knock or detonation tendencies of gasoline. TEL act as a negative catalyst. anti-knock fuel did not fade once tetraethyl lead was discovered. In Europe, iron pentacarbonyl was once used as an anti-knock agent in petrol in place of tetraethyllead. The predominant use for tetraethyl lead is as an octane improver, or "anti-knock" additive, in gasolines intended as fuel for internal combustion engines. That additive: tetraethyl lead, also called TEL or lead tetraethyl, a highly toxic compound that was discovered in 1854. Lead is a toxic metal that interferes with anti-pollution devices and contributes to lead poisoning. tetraethyl lead — [ˌtɛtrə i:θʌɪl] noun Chemistry an oily organic compound of lead, used as an anti knock agent in leaded petrol …