Benzyl alcohol and sodium benzoate are obtained by the action of sodium hydroxide on benzaldehyde. This reaction is known as

Compound '$X$' (molecular formula $C_3H_8O$) reacts with acidic potassium dichromate to give product '$Y$' (molecular formula $C_3H_6O$). '$Y$' gives a silver mirror test. When '$Y$' is reacted with aqueous $NH_2CONHNH_2$ and sodium acetate,it gives product '$Z$'. What is the structure of '$Z$'?

Which reagent turns pink in the presence of an aldehyde?

Which product is not formed in the following reaction $:-$ $CH_3CHO + CH_3-CH_2-CHO \xrightarrow[\text {(ii) } \Delta]{\text {(i) } NaOH}$

The major product $(Z)$ of the following chemical reaction is

Aldol condensation will not be observed in