Which of the following tests is $NOT$ shown by acetaldehyde?

Select the reaction with the correct major product.

Clemmensen reduction involves the conversion of $ >C=O $ to $ >CH_2 $ in the presence of:

$CH_3-CO-CH_3 + [O] \xrightarrow{SeO_2} P + Se + H_2O$. What is $P$ here?

$p$-Cresol reacts with chloroform in an alkaline medium to give compound $A$,which on addition of hydrogen cyanide forms compound $Y$. Acidic hydrolysis of $Y$ yields a chiral carboxylic acid. What is the structure of the carboxylic acid?

$CH_3-CO-CH_3$ $\xrightarrow{NaCN/HCl} A$ $\xrightarrow{H_3O^{+}/\Delta} B$. In the above sequence of reactions,$A$ and $B$ are: