Which is the most acidic of the following?

What type of bonds are formed between two carbon atoms in acetylene?

Give the hydrogenation and halogenation reactions of alkynes.

The compound $C_3H_4$ has a triple bond,which is indicated by its reaction with

An unknown compound $X$ is an unsaturated hydrocarbon. It reacts with $HgSO_4$ and $H_2SO_4$ to give compound $(B)$. Compound $(B)$ on oxidation gives compound $(C)$. Compound $(C)$ on reaction with $NaOH$ and soda lime gives methane. Identify $A$ (which is $X$),$B$,and $C$ by providing the chemical reactions.

Identify the correct order of acidic strength for the following hydrocarbons: