Toluene reacts with chromyl chloride to form $.....$.

What is $Z$ in the following reaction sequence?
$C_6H_5NH_2$ $\xrightarrow[(i) NaNO_2 + HCl / 273 \ K]{(ii) H_3PO_2 + H_2O}$ $\xrightarrow[(iii) CO, HCl, \text{anhydrous } AlCl_3/CuCl]{} Z$

Chromyl chloride converts a methyl group to a chromium complex,which on acid hydrolysis gives the corresponding aldehyde. This reaction is called:

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?

Identify the product $Y$ in the following series of reactions.
$4-$Nitrotoluene $\xrightarrow[(CH_3CO)_2O / CrO_3]{273-278 \ K} X$ $\xrightarrow{H_3O^{+} / \Delta} Y$

The reagents used in the Etard reaction $(I)$ and the Stephen reaction $(II)$ are: