Question

(i) Write the equation for the laboratory preparation of ethyne (acetylene) from calcium carbide.
(ii) What is the special feature of the structure of ethyne?
(iii) What would you see when ethyne is bubbled through a solution of bromine in carbon tetrachloride?
(iv) Name the addition product formed between ethene and water.

Answer 1

(i) $\underset{\mathrm{Calcium}\mathrm{carbide}}{{\mathrm{CaC}}_2}+{\mathrm{H}}_2\mathrm{O}\to \underset{\mathrm{Ethyne}}{{\mathrm{C}}_2{\mathrm{H}}_2}+\mathrm{Ca}{\left(\mathrm{OH}\right)}_2$

(ii) The special feature of the structure of ethyne is that it contains a triple bond between the two carbon atoms.

(iii) When ethyne is bubbled through bromine solution (which is orange in colour) in carbon tetrachloride, then the bromine solution eventually loses it colour.

(iv) Ethanol