RCHO represents which kind of formula?

RCHO represents a general formula for aldehydes. This particular notation indicates that a molecule consists of a carbonyl group (C=O) with a hydrogen atom (H) attached to the carbon atom, which is also connected to another group (represented here generically as "R").

In chemistry, a general formula provides a way to represent a class of compounds, giving insight into their structure while maintaining a degree of flexibility in the representation of reactive groups. While the structural formula gives a more detailed view of the connectivity of atoms, and an empirical formula expresses the simplest whole-number ratio of the elements in a compound, the general formula encapsulates the specific functional group characteristics shared among compounds in that class.

Thus, the correct answer effectively highlights how RCHO acts as a placeholder for aldehydes, summarizing their structural characteristics without pinpointing a specific compound, thus qualifying as a general formula.