Which among the following reagents is used in the Rosenmund reduction?

For the reaction below, the structure of the product $Q$ is:

What is the product formed by the reaction of chromyl chloride and toluene?

In which of the following pairs is the reactant correctly matched with the reagent that would form benzaldehyde as the product?

Which of the following compounds is obtained by dry distillation of calcium propionate?

Identify the product obtained in the following reaction:
$C_6H_6 \xrightarrow[\text{Anhydrous } AlCl_3, \text{high pressure}]{CO, HCl} \text{product}$