viscosity
Viscosity measures a fluids resistance to flow the higher the viscosity, the slower the flow of the material. One factor that affects viscosity is the strength of the intermolecular forces in the material. Molecules that exhibit higher intermolecular forces tend to have higher viscosities. Temperature also influences viscosity. A higher temperature results in a decrease in viscosity, since molecules are moving faster and the intermolecular forces are more easily disrupted. Most cooking oils are more viscous than water, but when heated, the viscosity decreases and the oil spreads more easily. Motor oils are ranked by viscosity. Lower viscosity oils provide less drag on the engine, but they are also used up faster than a higher-viscosity material.