An ester X (C4H8O2) is hydrolysed with aqueous NaOH to give a sodium salt Y and an alcohol Z. Z gives a yellow precipitate with NaOH/I2, and oxidation of Z with excess acidified K2Cr2O7 gives the same acid that is present in Y. X is

MolSynapse / Question bank / Structural Identification and Practical Organic Chemistry / Structure determination from reaction sequences

JEE Advanced levelSingle correct optionDifficulty 3 of 3si120

An ester X ( $C X_{4} H X_{8} O X_{2}$ ) is hydrolysed with aqueous $NaOH$ to give a sodium salt Y and an alcohol Z. Z gives a yellow precipitate with $NaOH / I X_{2}$ , and oxidation of Z with excess acidified $K X_{2} Cr X_{2} O X_{7}$ gives the same acid that is present in Y. X is

Amethyl propanoate
Bpropyl methanoate
Cpropan-2-yl methanoate
Dethyl ethanoate

Answer: D

The

C X_{4} H X_{8} O X_{2}

esters are ethyl ethanoate, methyl propanoate, propyl methanoate and propan-2-yl methanoate. Z gives iodoform, so Z is ethanol or propan-2-ol, and ethanol alone is oxidised to an acid. The acid from ethanol is

CH X_{3} COOH

, equal to the acid of Y for ethyl ethanoate only. Propan-2-ol would give a ketone.

Practice Structural Identification and Practical Organic Chemistry More on Structure determination from reaction sequences

Previous questionNext question

An ester X (CX4​HX8​OX2​) is hydrolysed with aqueous NaOH to give a sodium salt Y and an alcohol Z. Z gives a yellow precipitate with NaOH/IX2​, and oxidation of Z with excess acidified KX2​CrX2​OX7​ gives the same acid that is present in Y. X is

Answer: D

More questions on Structure determination from reaction sequences

An ester X ( $C X_{4} H X_{8} O X_{2}$ ) is hydrolysed with aqueous $NaOH$ to give a sodium salt Y and an alcohol Z. Z gives a yellow precipitate with $NaOH / I X_{2}$ , and oxidation of Z with excess acidified $K X_{2} Cr X_{2} O X_{7}$ gives the same acid that is present in Y. X is