Chemistry A-Level
Combined C=O and O–H evidence
What Combined C=O and O–H evidence means in Chemistry A-Level, as defined for OCR.
Definition of Combined C=O and O–H evidence
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Reference: OCR
Both the C=O peak and the broad O–H peak must be present together to identify a carboxylic acid, since a single C=O peak suggests an aldehyde, ketone, ester or acid chloride instead.
Topics that use Combined C=O and O–H evidence
- Analytical techniques (OCR A-Level)
Related terms
- Absorption and re-emission of infrared radiation
- Absorption of infrared radiation
- Absorption of infrared radiation by bond vibrations
- Bond stretching and bending
- Broad peak shape caused by hydrogen bonding
- Change in dipole moment
- Changes to energy usage
- characteristic absorption bands
Using Combined C=O and O–H evidence in the exam
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