Answer:
The Molecular formula of the 4-chloropthalic acid:
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Step-by-step explanation:
In 4-chloropthalic acid the main the skeleton in the molecule is benzene ring.
In benzoic acid the one more carboxylic group is present at ortho position and one chloro group is present at para position of the ring.
The structure of the 4-chloropthalic acid is given in an image.