Shortages (in the technical sense) may be caused by: 1  Price ceilings, a type of price control which involves a government-imposed limit on the price of a product service. 2  Anti-price gouging laws. 3  Government ban on the sale of a product or service, such as prostitution or certain recreational drugs.
Noun. 1. addition reaction-a chemical reaction in which one molecule is added to another. chemical reaction, reaction - (chemistry) a process in which one or more substances are changed into others; there was a chemical reaction of the lime with the ground water. 1  Facebook. 2  Twitter.
The aldol reaction is a means of forming carbonâcarbon bonds in organic chemistry. Discovered independently by Charles-Adolphe Wurtz and Alexander Borodin in 1872, the reaction combines two carbonyl compounds (the original experiments used aldehydes) to form a new Î²-hydroxy carbonyl compound. typical modern aldol addition reaction, shown above, might involve the nucleophilic addition of a ketone enolate to an aldehyde. Once formed, the aldol product can sometimes lose a molecule of water to form an Î±,Î²-unsaturated carbonyl compound. This is called aldol condensation.