What is the major product formed when propyne reacts with aqueous $HgSO_4$ in the presence of $H_2SO_4$?

Choose the sequence of steps that describes the best synthesis of but$-1$-ene from ethanol.

Identify the alkyne in the following sequence of reactions:
Alkyne $\xrightarrow{\text{H}_2, \text{Lindlar's catalyst}} A$ $\xrightarrow{\text{Ozonolysis}} B \text{ (only)}$
Given that $B$ is obtained from $\text{CH}_2=\text{CH}_2$ via the Wacker process.

When $CH_3CH_2CH_2CHCl_2$ is treated with $2 \ g$ equivalent of $NaNH_2$,the product formed is:

The correct order for acid strength of compounds $CH \equiv CH$,$CH_3 - C \equiv CH$,and $CH_2 = CH_2$ is as follows:

Which of the following compounds on hydration (addition of $H_2O$) with $H_2SO_4/HgSO_4/H_2O$ gives an aldehyde as the major product?