Benzaldehyde can be converted to benzyl alcohol in concentrated aqueous NaOH solution using

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Benzaldehyde can be converted to benzyl alcohol in concentrated aq. NaOH solution using formaldehyde. This reaction is known as Cannizzaro reaction, where one molecule of benzaldehyde is reduced to alcohol while formaldehyde is oxidised to carboxylic acid salt. Aldehydes, which do not have an -hydrogen atom undergo this type of reaction.