Which of the following does not effect the transformation shown below?
$R_2C=O \rightarrow R_2CH_2$

$2CD_2=O + OH^- \xrightarrow{\quad} X + Y$ ($Y$ is an alcohol and $D$ is deuterium). Identify $X$ and $Y$.

In Tollen's test for aldehyde,the overall number of electron$(s)$ transferred to the Tollen's reagent formula $[Ag(NH_{3})_{2}]^{+}$ per aldehyde group to form silver mirror is $......$. (Round off to the Nearest integer)

The major product formed in the following reaction sequence is $CH_3-CH=CH_2$ $\xrightarrow[\substack{(iii) \ CH_3-CH_2-CHO \\ (iv) \ CrO_3}]{\substack{(i) \ HBr, \text{ peroxide} \\ (ii) \ Mg}}$

In the reaction $CH_3CHO + HCN \to CH_3CH(OH)CN$,a chiral center is generated. The product will be ........

Which of the following reactions are incorrect?
$(a)$ $CH_2(COOH)_2 \xrightarrow{\Delta} CH_3COOH + CO_2$
$(b)$ Aniline $\xrightarrow{CH_3Cl/AlCl_3}$ $p$-chloroaniline
$(c)$ Phenol $\xrightarrow{CHCl_3 + aq. NaOH}$ Salicylic acid
$(d)$ $CH_3CHO + NaHSO_3 \rightleftharpoons CH_3CH(OH)SO_3Na$
$(e)$ Benzene $\xrightarrow{CO, HCl, Anhydrous AlCl_3/CuCl}$ Benzaldehyde