Answer:
Functional groups are groups of atoms that occur within organic molecules and confer specific chemical properties to those molecules. When functional groups are shown, the organic molecule is sometimes denoted as “R.” For example, ethanol is typically drawn like this:
In order to condense the structure and focus on the hydroxyl group (the oxygen and hydrogen bound to the second carbon), everything besides the hydroxyl group would replaced with an R, as follows:
Step-by-step explanation: