To identify the functional groups present in a given organic compound using infrared IR spectroscopy, you can follow these steps:1. Sample preparation: Obtain a small amount of the organic compound, either in solid, liquid, or gaseous form. If the sample is solid, you can prepare a KBr pellet by grinding the sample with potassium bromide and pressing it into a thin, transparent disk. If the sample is liquid, you can place a drop of the liquid between two salt plates e.g., NaCl or KBr . If the sample is gaseous, you can fill a gas cell with the sample.2. Record the IR spectrum: Place the prepared sample in the IR spectrometer and record the spectrum. The IR spectrometer will pass infrared light through the sample and measure the absorbance of the light at various wavelengths. The resulting spectrum will display the absorbance or transmittance as a function of wavenumber cm .3. Interpret the IR spectrum: Analyze the spectrum by looking for characteristic absorption bands that correspond to specific functional groups. Some common functional groups and their corresponding IR absorption bands are: - O-H alcohol or phenol : Broad absorption around 3200-3600 cm - O-H carboxylic acid : Broad absorption around 2500-3300 cm, often with a sharp C=O peak around 1700 cm - N-H amine : Medium to broad absorption around 3300-3500 cm, often as two peaks for primary amines - C-H alkane : Absorption around 2850-3000 cm, often with multiple peaks - C=C alkene : Absorption around 1600-1680 cm - CC alkyne : Absorption around 2100-2260 cm - C=O carbonyl : Sharp absorption around 1650-1750 cm, with the exact position depending on the type of carbonyl e.g., ketone, aldehyde, ester, amide - CN nitrile : Absorption around 2210-2260 cm - C-N amine : Absorption around 1000-1250 cm4. Confirm the functional groups: Based on the observed absorption bands, determine the functional groups present in the organic compound. Keep in mind that some functional groups may have overlapping absorption bands, so it's essential to consider the entire spectrum and the relative intensities of the peaks. If necessary, you can use other analytical techniques e.g., NMR spectroscopy, mass spectrometry to confirm the functional groups and the overall structure of the compound.By following this experimental procedure and interpreting the obtained IR spectra, you can successfully identify the functional groups present in a given organic compound.