Exams › NEET › Chemistry

Glucose reacts with one molecule of phenyl hydrazine to give phenyl hydrazone. When warmed with excess of phenylhydrazine, the secondary alcoholic group adjacent to the aldehyde group is oxidised by another molecule of phenylhydrazine to a ketonic group. With this ketonic group, the third molecule of phenylhydrazine condenses to glucosazone. Therefore, the value of X is 3.

1. CHO + H2NNHCH5 → CH = NNHC6H5
2. CHOH → CHOH
3. (CHOH)3 → (CHOH)3
4. CH2OH → CH2OH

Correct answer: CHO + H2NNHCH5 → CH = NNHC6H5

Solution

The reaction described involves the formation of phenylhydrazone from glucose, where the aldehyde group reacts with phenylhydrazine. This corresponds to option A.

Related NEET Chemistry questions

• Among the following organic acids, the acid present in rancid butter is:
• Which of the following is incorrect about polysaccharides? I. These are amorphous solids. II. These are sparingly soluble in water. III. These are sugars
• Which of the following has been used in the manufacture of non-inflammable photographic films?
• Incorrect statement about given carbohydrate is
• Which of the following cyanohydrins on hydrolysis give an optically active acid giving iodoform reaction?
• Which of the following is a polysaccharide?

⚔️ Practice NEET Chemistry free + battle 1v1 →