What are molecules that are insoluble in water and contain hydrogen, oxygen, and carbon called?

Molecules that are insoluble in water and consist of hydrogen, oxygen, and carbon are classified as lipids. Lipids are a diverse group of compounds that include fats, oils, waxes, and steroids. One of their defining characteristics is their hydrophobic nature, meaning they do not dissolve in water due to their nonpolar structure, which predominantly features long hydrocarbon chains or rings.

Lipids play essential roles in biological systems, such as serving as energy storage molecules, forming cell membranes (phospholipids), and acting as signaling molecules (steroids). Their insolubility in water allows them to create barriers and compartments within cells, which is crucial for maintaining cellular organization and function.

Carbohydrates, on the other hand, are typically soluble in water due to their polar hydroxyl (-OH) groups. Alcohols, which are organic compounds containing one or more hydroxyl groups, are often soluble in water because the hydroxyl groups interact favorably with water molecules. Proteins are complex macromolecules made up of amino acids that can exhibit varying degrees of solubility in water, depending on their structure and the properties of their constituent amino acids.