What is a polymer and what is a monomer?

What is a polymer and what is a monomer?

• A. A polymer is a large molecule made by joining many repeating units called monomers
• B. A polymer is a small molecule used to build polymers
• C. A polymer is a mixture of monomers
• D. A polymer is a single repeating unit

Answer: (A)

Polymers are large molecules built by joining many repeating units called monomers. The monomer is the small molecule that acts as the building block for the polymer, and many of these units connect to form a long chain, giving a big macromolecule. For example, ethene monomers can link to form polyethylene, where each repeating unit along the chain is the ethene-derived unit. This is the best description because it captures both the scale (a large molecule) and the process (joining many repeating monomer units). The idea that a polymer is a small molecule, a mixture of monomers, or a single repeating unit doesn’t fit the definition: a small molecule is a monomer, a polymer isn’t just a mixture of separate monomers, and a single repeating unit would be a monomer, not the polymer as a whole.

Polymers are large molecules built by joining many repeating units called monomers. The monomer is the small molecule that acts as the building block for the polymer, and many of these units connect to form a long chain, giving a big macromolecule. For example, ethene monomers can link to form polyethylene, where each repeating unit along the chain is the ethene-derived unit.

This is the best description because it captures both the scale (a large molecule) and the process (joining many repeating monomer units). The idea that a polymer is a small molecule, a mixture of monomers, or a single repeating unit doesn’t fit the definition: a small molecule is a monomer, a polymer isn’t just a mixture of separate monomers, and a single repeating unit would be a monomer, not the polymer as a whole.