Name the following reaction: $C_6H_5COCl + H_2 \xrightarrow{Pd-BaSO_4} C_6H_5CHO + HCl$

The major product obtained in the reaction of isobutylbenzene with acetic anhydride in the presence of anhydrous $AlCl_3$ is:

Which of the following reactions will yield benzaldehyde as a product?

In the following reaction,product $P$ is: $RCOCl \xrightarrow{H_2, Pd-BaSO_4} P$

In the following sequence of reactions,what is the end product $(D)$?
$C_2H_5Br$ $\xrightarrow{KCN} A$ $\xrightarrow{H_3O^{+}} B$ $\xrightarrow{LiAlH_4} C$ $\xrightarrow[573 \ K]{Cu} D$.

Collin's reagent is