(a) What is a monomer? (b) Which of these molecules can be used as a monomer: ethanol, ethene (also called ethylene), methane?

Monomers are small, simple molecules that can chemically bond to form larger structures known as polymers. In polymer chemistry, monomers serve as the building blocks for creating various materials, such as plastics and fibers. Understanding the distinction between monomers and polymers is essential for identifying which substances can participate in polymerization reactions.

Hydrocarbons are organic compounds consisting entirely of hydrogen and carbon. They can be classified into alkanes, alkenes, and alkynes based on the types of bonds between carbon atoms. Ethene (ethylene) is an alkene with a double bond, making it a suitable candidate for polymerization, while ethanol and methane do not have the same reactivity for forming long-chain polymers.

Polymerization is the chemical process through which monomers link together to form polymers. There are two main types: addition polymerization, where unsaturated monomers like alkenes react to form a polymer, and condensation polymerization, which involves the elimination of small molecules like water. Recognizing the conditions and types of monomers that can undergo polymerization is crucial for determining their suitability as monomers.