Final answer:
The assertion that synthetic oil has different sized molecules is false. Synthetic oils are engineered to have a consistent and uniform molecular structure, enhancing performance and viscosity.
Step-by-step explanation:
The statement about synthetic oil having different sized molecules is false. Synthetic oils are specifically engineered to have uniform molecular sizes compared to conventional oils, which have a mixture of different sized hydrocarbon chains. This uniformity is one of the reasons synthetic oils offer better performance, including decreased engine wear, better viscosity performance at temperature extremes, and improved fuel efficiency.
During the refinement process, crude oil is separated into components of different chain lengths. The shorter chains are used for products like gasoline, while longer chains might be used in the production of lubricants or tars. Synthetic oils, however, are not a direct product of crude oil but are often built up from smaller molecules to create a product with a more predictable and uniform molecular structure.
The correlation between viscosity and molecular shape is significant. The more uniform molecular size in synthetic oils results in a consistent viscosity, leading to improved engine performance and protection.