$2Ph-CHO \xrightarrow{OH^-} Ph-CH_2OH + PhCOO^-$
Which is the slowest step in the above Cannizzaro reaction?

The $Wolff-Kishner$ reduction is used for which of the following?

Identify the product $A$ in the following reaction:
$\text{Substrate} \xrightarrow{MnO_2} A$
(The substrate is a benzene ring with a $-OH$ group,a $-COOH$ group,and a $-CH(CH_2CH_3)CHO$ group attached to it.)

Consider all possible isomeric ketones,including stereoisomers of $MW = 100$. All these isomers are independently reacted with $NaBH_4$ ($NOTE$: stereoisomers are also reacted separately). The total number of ketones that give a racemic product$(s)$ is/are

Which of the following compounds will not react with $NaHSO_3$?

The best reagent to carry out the following conversion is:
$3$-hydroxyethylcyclopentane-$1$-carbaldehyde $\rightarrow$ $1$-ethyl-$3$-methylcyclopentane (with a hydroxy group on the ethyl side chain).
(Note: The image shows the reduction of an aldehyde group $-CHO$ to a methyl group $-CH_3$ while keeping the secondary alcohol $-CH(OH)CH_3$ intact.)