Chemistry Aldehydes & Ketones BUMHS 2022
PMDC Verified Question 42 of 94
Dry heating of calcium acetate gives which of the following?
A
Acetaldehyde
B
Acetic acid
C
Acetone
D
Ethane
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option C: Acetone
Concept:

The dry distillation (strong heating without solvent) of calcium salts of carboxylic acids is a classic preparatory method for symmetric ketones.

Formula:

$$ (CH_3COO)_2Ca \xrightarrow{\Delta} CH_3-CO-CH_3 + CaCO_3 $$

Solution:

  • Calcium acetate consists of a calcium ion bonded to two acetate (\( CH_3COO^- \)) molecules.


  • Upon dry heating, the molecule undergoes thermal decomposition, eliminating a molecule of calcium carbonate (\( CaCO_3 \)).


  • The remaining fragments collapse into a single molecule containing a carbonyl bonded to two methyl groups, which is Acetone (Propanone).


Why other options are incorrect:

Acetaldehyde would require heating a mixture of calcium acetate and calcium formate. Acetic acid and ethane are not thermal decomposition products of this salt.

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