Viscosity is a measure of what property of oil?

Viscosity is best described as the internal resistance to flow of a fluid, including oil. This property indicates how readily a fluid can flow; a fluid with high viscosity resists motion because its molecular makeup offers more internal friction. For example, honey has a higher viscosity compared to water, meaning it flows more slowly and with greater resistance.

Understanding viscosity is crucial in various applications, such as lubrication, where the right viscosity ensures effective operation and protection of machinery. It impacts the performance of oils under different temperature conditions, where a change in viscosity can influence how effectively an oil can do its job as a lubricant or hydraulic fluid.

The other options, while relevant to different properties of oils, do not pertain directly to viscosity. Chemical stability relates to the oil’s ability to resist degradation over time, thermal conductivity refers to how well a substance can conduct heat, and specific gravity measures the density of the oil compared to water. Each of these properties is important in its own right, but they do not represent the resistance to flow that characterizes viscosity.