A Level Chemistry OCR Practice Exam

What describes the process of addition polymerization?

1. Creating energy by breaking bonds

2. Adding unsaturated molecules to form long chains

3. Removing solvents from a reaction

4. Combining two different types of polymers

The correct answer is: Adding unsaturated molecules to form long chains

The process of addition polymerization involves the reaction of unsaturated monomers—typically alkenes or alkynes—where the double or triple bonds in these monomers open up to allow them to bond together and form long chains. This method results in a polymer without the loss of any small molecules, effectively building larger structures from the smaller units. The formation of these long chains is a defining characteristic of addition polymerization, making it an essential reaction in the synthesis of many types of plastics and synthetic materials. In contrast, the other options describe different processes. Creating energy by breaking bonds does not align with how addition polymerization works, as this process focuses on the formation of bonds rather than the breaking of them. Removing solvents refers to methods commonly used in other types of reactions or in purification processes, which does not characterize addition polymerization. Lastly, combining two different types of polymers is more aligned with copolymerization rather than the addition of unsaturated monomers to create a single type of polymer.