The ir spectrum of benzilic acid is shown below. for each peak indicated by the blue boxes, select the bond represented by the frequency.

Below is the structure of Benzilic Acid and IR spectrum. First common thumb rule for elucidating IR spectrum is to find a broad and intense signal between 1690-1800 cm⁻¹, If present! Then its for Carbonyl group. Secondly, watch for broad peak around 3400-3600 cm⁻¹, peak at this frequency is given by the -OH (Hydroxyl) group of Alcohols, andthe broadness is due to Association effect (Hydrogen bonding). Third, aif a wide band between 2500-3300 cm⁻¹ is present it shown -OH of carboxylic acid.

Result:
           Carbony Group =  1640 cm⁻¹

          Carboxyl -OH Group  =  2950 cm⁻¹

          Alcohol -OH  =  3400 cm⁻¹

Decomposition is the cycle at which bacteria breaks down any organic material into the soil