UV-Vis spectroscopy is a technique used to study the absorption of light by molecules in the ultraviolet-visible region of the electromagnetic spectrum wavelengths ranging from 200 nm to 800 nm . This technique can be used to identify functional groups in organic compounds based on their characteristic absorption peaks.In the case of carboxylic acids, the presence of the carboxyl functional group -COOH can be identified by analyzing the absorption peaks in the UV-Vis spectrum. The carboxylic acid functional group typically exhibits absorption peaks in the range of 170-176 nm. This absorption peak is due to the * electronic transition in the carbonyl group C=O present in the carboxylic acid functional group.The significance of the absorption peak at a wavelength of 170-176 nm is that it indicates the presence of the carbonyl group in the carboxylic acid functional group. This peak is characteristic of carboxylic acids and can be used to confirm the presence of the carboxylic acid functional group in a given organic compound.It is important to note that UV-Vis spectroscopy alone may not be sufficient to conclusively identify the presence of a carboxylic acid functional group, as other functional groups may also exhibit absorption peaks in the same region. Therefore, it is recommended to use complementary techniques, such as infrared IR spectroscopy, nuclear magnetic resonance NMR spectroscopy, or mass spectrometry MS , to confirm the presence of the carboxylic acid functional group in a given organic compound.