Which of the following is not a polymer?

• A. $\mathrm{Glucose}$
• B. $\mathrm{Polyethylene}$
• C. $\mathrm{Polystyrene}$
• D. $\mathrm{Cellulose}$

Answer: (A)

Verified step by step guidance

1. Step 1: Understand the definition of a polymer. A polymer is a large molecule composed of repeating structural units called monomers, which are covalently bonded together in a chain or network.
2. Step 2: Identify each compound's nature. Polyethylene, polystyrene, and cellulose are all polymers because they consist of repeating monomer units: polyethylene is made from ethylene monomers, polystyrene from styrene monomers, and cellulose from glucose monomers linked in a chain.
3. Step 3: Analyze glucose. Glucose is a small molecule (a monosaccharide) and serves as a monomer unit rather than a polymer itself. It does not consist of repeating units linked together.
4. Step 4: Compare glucose with the other options. Since glucose is a single monomer unit and not a chain of repeating units, it does not meet the criteria of a polymer.
5. Step 5: Conclude that glucose is not a polymer, while polyethylene, polystyrene, and cellulose are polymers.