A molecular formula is #C_4H_8O_2#. It has a degree of unsaturation of 1. Also it has an #OH# group, #CH_3# (sp3) group, and #C=O# group. What functional groups can be present?

1 Answer
Feb 27, 2016

Carboxylic acid, alcohol, ketone, and aldehyde

Explanation:

A saturated hydrocarbon is one in which there exist no double bonds and no rings within the structure. In other words, if you had a 6-carbon molecule, it would be a chain of 6 carbons and each carbon would be attached to 4 different atoms.

Conversely, an unsaturated compound WILL have a double bond, triple bond, a ring, or any combination of the three depending on the degree of unsaturation.

Degree of unsaturation can be calculated using the following equation:

#DU= C-H/2+N/2-X/2+1#

Where #DU# is the degree of unsaturation, #C# is the number of carbons, #H# is the number of hydrogens, #X# is the number of halides, and #N# is the number of nitrogens in the compound.

Based on the formula given in the problem, #C_4 H_8 O_2#, #DU# would be:

#DU= 4-8/2+0/2-0/2+1 = 1#

This implies that there is one double bond, or one ring present in the molecule. Since #C=O# is provided, this double bond is the only cause for unsaturation in the molecule.

A few possibilities given the conditions of the problem would be:
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