Question

Pyrolysis of ethyl acetate gives:
A. $$C{H}_{3}COC{H}_3$$
B. $$C{H}_2=C{H}_2$$
C. $$C{H}_2=C=O$$
D. $$C{H}_3-CHO$$

Answer 1

Hint: Pyrolysis is the thermal decomposition of a substance at a particular temperature in an inert atmosphere, it involves a change of chemical composition. On decomposition of ester carboxylic acid and ethylene are formed.

Complete step by step answer:
Pyrolysis of ethyl acetate $$\left(C{H}_{3}COOC{H}_{2}C{H}_3\right)$$ gives ethane and acetic acid.
$$\underset{\left(ethylacetate\right)}{\left(C{H}_{3}COOC{H}_{2}C{H}_3\right)}\underset{Pyrolysis}{\overset{\mathrm{\Delta }}{\to }}\underset{\left(aceticacid\right)}{C{H}_{3}COOH}+\underset{\left(ethylene\right)}{C{H}_2=C{H}_2}$$
Ethyl acetate is heated in the presence of liquid nitrogen and glass wool.
Pyrolysis reaction is converting esters containing a $\beta -$hydrogen atom into the corresponding carboxylic acid and alkene. The reaction is a unimolecular elimination and operates in a syn-elimination. The mechanism involves a unimolecular six – centered transition state producing equimolar ethylene and acetic acid.
Mechanism of pyrolysis of ethyl acetate


Therefore, the correct option is (D).

Note:
Ethyl acetate is a colorless liquid and is commonly known as ethyl ethanoate. Ethyl acetate is a polar aprotic solvent and it is a standard solvent. It is an important chemical compound. It is used especially for paints, varnishes, lacquers, cleaning and perfumes. The thermal decomposition of ethyl acetate follows a first order unimolecular reaction. The kinetic and thermodynamic parameters are obtained experimentally by applying the Arrhenius equation at a temperature range from ${400}^{\circ }$ to ${600}^{\circ }$C. The products from the pyrolysis of ethyl acetate were analyzed by gas chromatography.