Carbonyl group
= Carbonyl group
{title2=$\mathrm{C=O}$}
A <carbonyl group> contains a <carbon>–<oxygen> double <covalent bond>. It occurs in <aldehydes> and <amides>. https://openstax.org/books/organic-chemistry/pages/12-7-interpreting-infrared-spectra[McMurry: carbonyl-containing groups]{ref}