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.
ADDITION & CONDENSATION. The Aldol addition reaction involves the addition of Î±-carbon of an enolizable aldehyde or ketone to the carbonyl group of another aldehyde or ketone and thus by giving a Î²-hydroxy carbonyl compound also known as an aldol (indicating both aldehyde and alcohol groups).