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Question
An organic compound having the molecular formula C3H6O can exist in the form of two isomers A and B having different functional groups. The isomer A is a liquid which is used as a solvent for nail polish. The isomer B is also a liquid. An aqueous solution of one of the lower homologues of B is used for preserving biological specimens in the laboratory
(a) What is compound A?
(b) Write the electron-dot structure of A.
(c) What is compound B?
(d) Write the electron-dot structure of B.
(e) Name the lower homologue of compound B which is used in preserving biological specimens.
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Solution
(a) The isomer A is propanone (acetone).
(b) The electron-dot structure of propanone is::

(c) The isomer B is propanal.
(d)The electron-dot structure of propanal is:

(e) Methanal or formaldehyde is the lower homologue of compound B, which is used to preserve biological specimens.
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