$PCl_5$ reacts with a compound containing

What is the $IUPAC$ name of the organic compound formed in the following chemical reaction?
Acetone $\xrightarrow[(ii) H_2O, H^{+}]{(i) C_2H_5MgBr, \text{dry Ether}}$ Product

In the reaction sequence:
$\text{Ethanol}$ $\xrightarrow{PCl_5} X$ $\xrightarrow{\text{alc. } KOH} Y$ $\xrightarrow[H_2O, \Delta]{H_2SO_4, \text{room temp.}} Z$
The product $Z$ is:

The vapours of an alcohol $(X)$ are passed over $Cu$ heated at $300^{\circ} C$,where an alkene is formed as the product. The alcohol $(X)$ is expected to be $:-$

Write the structures of the isomers of alcohols with molecular formula $C_4H_{10}O$. Which of these will exhibit optical activity?

In which of the following reactions will a resonance-stabilized product be formed?