sentence: This can be used to gain information about the sample composition in terms of chemical groups present and also its purity (for example a wet sample will show a broad O-H absorption around 3200 cm −1 ).
modified: fix grammar: This can be used to gain information about the sample composition at terms of chemical groups present and also its purity (for example a wet sample will show a broad O-H absorption around 3200 cm −1 ).