$I.$ ${Sn}-{HCl}$ $II.$ ${Sn}-{NH}_{4} {OH}$ $III.$ ${Fe}-{HCl}$ ${IV} . {Zn}-{HCl}$ $V.$ ${H}_{2}-{Pd}$ $VI.$ ${H}_{2}-$ રેની નિકલ
In the above chemical reaction, intermediate $"X"$ and reagent/condition $"A"$ are

The unknown compounds $A$ and $B$ in the above reaction are :

$C{H_3}CN\xrightarrow{{Na + {C_2}{H_5}OH}}X\xrightarrow{{HN{O_2}}}Y\mathop {\xrightarrow{{{K_2}C{r_2}{O_7}}}}\limits_{{H_2}S{O_4}} Z$


