Final answer:
In the IR spectra, the carboxylic acid will have a strong absorption peak in the 1650-1750 cm-1 range, while the ester will have this peak shifted to a slightly lower wavelength. The carboxylic acid will also have a characteristic O-H stretching peak, which will be absent in the ester. Experimental results should match these expectations.
Step-by-step explanation:
When comparing the IR spectra of a carboxylic acid and an ester, we can expect to see a clear change in the major IR peaks. The carboxylic acid will have a strong absorption peak in the 1650-1750 cm-1 range, corresponding to the carbonyl double bond. In the ester, this peak will be shifted to a slightly lower wavelength. Additionally, the carboxylic acid will have a characteristic O-H single bond stretching absorbance peak in the lower wavelength range, which will be absent in the ester.
Experimental results should match these expected major IR peaks. The presence of the carbonyl double bond peak in the 1650-1750 cm-1 range and the absence of the O-H stretching peak in the ester would indicate a successful conversion from carboxylic acid to ester. It is important to note that any other minor peaks or changes in intensity could be present due to impurities or different reaction conditions.
To summarize, the major IR peaks expected in the carboxylic acid IR spectrum are the carbonyl double bond peak in the 1650-1750 cm-1 range and the O-H stretching peak. In the ester IR spectrum, the carbonyl double bond peak will be shifted to a slightly lower wavelength and the O-H stretching peak will be absent.