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.
Alkynes: Addition Reactions. The principal reaction of the alkynes is addition across the triple bond to form alkanes. These addition reactions are analogous to those of the alkenes. Hydrogenation. Alkynes undergo catalytic hydrogenation with the same catalysts used in alkene hydrogenation: platinum, palladium, nickel, and rhodium.