A-LevelChemistryHydrocarbonsOct/Nov 2017Paper 4 Q716 Marks
Calcium carbide, CaC2, reacts readily with water, forming ethyne, C₂H₂, and a sparingly soluble white ionic compound. (a)(i) Write an equation for this reaction. (a)(ii) Draw a 'dot-and-cross' diagram for the carbide ion, C22-. Show outer electrons only. Ethyne is the simplest member of the alkyne homologous series. H—C≡C—H ethyne Propyne, C3H4, and butyne, C₄H₁, are the next two members of the series.
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