What causes surface tension 14 Is off a ducks back but thoro

What causes surface tension? 14. Is off a duck\'s back but thoroughly wets a head of r. What do these observations reveal about the 5Water rol chemical nature of these two surfaces? Why do raindrops not assume triangular or cubic shapes? 16. 7. How does perspiration cool the skin on a person\'s body? 18 Why does the surface of water in a glass test tube curve upward at the edges? 9. Automobile engines are designed to be lubricated with motor oils of specific viscosities. These are rated from the lowest viscosity of 5 W up to the highest viscosity of 70 W. What can you conclude about the intermolecular attractions in an oil rated 10 W? 20. What is the essential difference between boiling and evaporation? 21. Water in a truck\'s radiator can get hotter than 100 °C when the radiator is sealed tightly. How is it possible for water to exist as a liquid at temperatures above its normal boiling point?

Solution

14)

Surface tension in liquids is the energy required to increase the surface area of liquids by a unit amount and it is caused by the difference between the forces acting on the molecules at the surface of the liquid and those acting on a molecule within the liquid.

Surface tension is higher for the molecules that have stronger intermolecular attractive forces.