Formaldehyde reacts with HCN (NaCN + HCl) to give a compound:
Correct answer: B. B
- A. A
- B. B
- C. C
- D. D
Explanation
The reaction of formaldehyde with HCN (sodium cyanide and hydrochloric acid) is an example of a nucleophilic addition reaction. The reaction takes place as follows:H2C=O + HCN → H2C(OH)(CN)The product formed is called hydroxymethyl cyanide, which is also known as formaldehyde cyanohydrin. In this product, the HCN has added to the carbonyl carbon of formaldehyde, forming a new carbon-carbon bond and creating an alcohol and nitrile group. Therefore, the correct option is B, which represents the structure of hydroxymethyl cyanide.
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About Aldehydes and Ketones
Aldehydes and ketones contain the polar carbonyl group, but aldehydes are generally more readily oxidised and more reactive than ketones. Coverage includes preparation by oxidation or reduction routes, nucleophilic addition of reagents such as hydrogen cyanide and bisulfite, and tests that distinguish aldehydes from ketones.
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