-OH group bonded to carbon
Defines alcohols and makes molecules polar
A hydroxyl group is an oxygen atom bonded to a hydrogen atom (-OH) and attached to a carbon skeleton. Because oxygen is strongly electronegative, the group is polar and forms hydrogen bonds with water, so molecules rich in hydroxyl groups, such as sugars, dissolve well. Hydroxyl groups define alcohols and take part in the condensation reactions that link monomers into polymers. Unlike the hydroxide ion (OH⁻), a hydroxyl group stays bound to its molecule and does not make a solution basic.