Give reasons:

Reactions involving Grignard reagent must be carried out under anhydrous condition.

Give reasons:

Alkyl halides are generally not prepared by free radical halogenation of alkane.

Convert the following:

Propene to propan-$1$-ol

Convert the following:

Benzyl alcohol to benzyl cyanide

Convert the following:

Ethanol to propane nitrile

Convert the following:

But-$1$-ene to $\mathrm{n}$-butyl iodide