Q.Complete the reaction: CaC2 + 2H2O -->

Ethyne is made industrially either by controlled, high-temperature (1773 K) partial oxidation of methane, or -- far more commonly -- by reacting calcium carbide with water at room temperature (CaC2 + 2H2O -> C2H2 + Ca(OH)2). In the laboratory, alkynes are also built by double dehydrohalogenation of a vicinal dihalide: the dihalide first reacts with alcoholic KOH to eliminate one HX, forming an alkenyl (vinylic) halide intermediate, and this intermediate then reacts with the much stronger base sodamide (needed because a vinylic C-H is far less reactive than an ordinary alkyl C-H) to eliminate the second HX, completing the triple bond. A separate method builds a LO …