Phenylmethanol can be prepared by reducing benzaldehyde with:

Which of the following reaction sequences would be the best for the synthesis of $2$-pentanone?

$L$ $\xrightarrow[(ii) H_3O^{\oplus}]{(i) PhMgBr} M$ $\xrightarrow{CrO_3 / H^{\oplus}} N$ $\xrightarrow{Ph_3P=CH_2} Ph_2C=CH_2$
$L$ in the above sequence of reaction is/are (where $L \neq M \neq N$)

Which of the following compounds is obtained when toluene is treated with $CrO_2Cl_2$ in the presence of $CS_2$ followed by acid hydrolysis?

Write the chemical reactions for the following conversions:
$1.$ $2$-Chloropropane to Propanone
$2.$ Propene to Propanone

Identify the product '$B$' in the following reaction: $\text{Isopropyl cyanide} \xrightarrow{SnCl_2, HCl} A \xrightarrow{H_3O^+} B + NH_4Cl$