Final answer:
Viscosity is the resistance of a liquid to flow. The viscosity of an oil can be determined based on factors such as intermolecular interactions, molecular size, and temperature. Motor oils have an SAE rating that describes their viscosity.
Step-by-step explanation:
Viscosity is the resistance of a liquid to flow. The viscosity of an oil can be determined by considering factors such as intermolecular interactions, molecular size, and temperature. Viscosity increases with stronger intermolecular interactions and larger molecular size. It also decreases with increasing temperature. In the case of motor oils, viscosity is described by an SAE rating, with lower numbers indicating lower viscosity.