(03) Chromophore and Auxochrome | Instrumental Methods of Analysis | Chromophore | Auxochrome Theory

Download the "Solution Pharmacy" Mobile App to Get All Uploaded Notes, Model Question Papers, Answer Papers, Online Tests and other GPAT Materials - https://play.google.com/store/apps/de... Chromophores and auxochromes are chemical groups or structural components within molecules that contribute to their color and absorption properties, particularly in the context of UV-visible spectroscopy. Chromophore: Definition: A chromophore is the part of a molecule responsible for its color due to its ability to absorb certain wavelengths of light. Characteristics: Chromophores usually contain a series of alternating double and single bonds or a conjugated system. This arrangement allows them to absorb light in the visible region, resulting in color. Examples: Common chromophores include certain organic functional groups like carbonyl groups (C=O), nitro groups (-NO2), and extended conjugated systems like double bonds in aromatic compounds or polyenes. Auxochrome: Definition: An auxochrome is a functional group in a molecule that, when attached to a chromophore, alters or enhances its color and the absorption of light. Role: Auxochromes typically facilitate the interaction between the chromophore and the solvent, influencing the intensity and wavelength of absorption. Examples: Common auxochromes include groups like -OH (hydroxyl), -NH2 (amine), and -NR2 (dialkylamino). These groups have lone pairs of electrons that can interact through hydrogen bonding or other interactions, shifting the absorption spectrum and often intensifying the color produced by the chromophore. Relationship: Chromophores are responsible for the color, while auxochromes modify or enhance that color by influencing the absorption spectrum of the chromophore. Auxochromes usually increase the ability of the chromophore to absorb light and contribute to the overall intensity of the color observed. In UV-visible spectroscopy, understanding the presence and interaction of chromophores and auxochromes in a molecule helps in interpreting the absorption spectra and predicting the colors of compounds based on their structural features. This knowledge aids in qualitative and quantitative analysis of substances, identification of compounds, and studying their electronic transitions. Get in touch with the solution by just clicking the following links- Facebook Group-   / solutionpharamcy   Mobile App - https://play.google.com/store/apps/de... New Channel (Pharmacy Dictionary)    / @pharmacydictionary   E-Mail for official and other work - [email protected] #solutionpharmacy #Pharmacologyclass #Pharmacognosyvideos #GPAT