In the example given, water has a viscosity of 1/100 of a poise. This property is called

• A. Boiling point
• B. Vapor pressure
• C. Surface tension
• D. Viscosity

Answer: (D)

Viscosity is the measure of a liquid’s resistance to flow. The statement uses a numerical value in poise to express how easily or slowly water flows; a smaller number means the liquid is thinner and flows more readily. Here, 1/100 of a poise equals 0.01 poise, which corresponds to water’s low viscosity and its ability to flow easily. The other properties describe different behaviors: boiling point is the temperature at which liquid turns to vapor, vapor pressure is the pressure exerted by vapor in equilibrium with the liquid, and surface tension is the cohesive force at a liquid’s surface. So the property being described is viscosity.