MHTCET 15 Apr 2026 Shift 1 Paper

Concept:Cannizzaro reaction is a disproportionation reaction of aldehydes without an $\alpha$-hydrogen atom in the presence of concentrated alkali.Explanation:Aldehydes that do not contain an $\alpha$-hydrogen atom, such as $\mathrm{HCHO}$ and $\mathrm{C}_6\mathrm{H}_5\mathrm{CHO}$, undergo the Cannizzaro reaction with concentrated $\mathrm{NaOH}$ or $\mathrm{KOH}$.In this reaction, one molecule of the aldehyde is reduced to the corresponding alcohol.The other molecule of the aldehyde is oxidised to the salt of the corresponding carboxylic acid.For example, formaldehyde reacts with sodium hydroxide as shown below:$$2\mathrm{HCHO} + \mathrm{NaOH} \rightarrow \mathrm{CH}_3\mathrm{OH} + \mathrm{HCOONa}$$Here, one $\mathrm{HCHO}$ molecule is reduced to methyl alcohol, $\mathrm{CH}_3\mathrm{OH}$.The other $\mathrm{HCHO}$ molecule is oxidised to sodium formate, $\mathrm{HCOONa}$, which is the sodium salt of formic acid.Therefore, some aldehydes are converted into the respective alcohols and the salts of the respective carboxylic acids.Answer:Option A: Some aldehydes are converted to the respective alcohols and the salt of the respective carboxylic acid.