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1. What evidence of capillary action have you seen outside of the laboratory?

2. What is the explanation for capillary action?

3. Where are surface films found?

4. What are three common effects of surface films?

5. Explain why cravenette cloth sheds water.

6. If a circular glass disc 10 cm. in diameter requires 50 grams of force to draw it from the water, what is the cohesion of water per square centimeter?

7. What is the weight in grams of 1 ccm. of water? of a liter of water?

8. Name five examples of adhesion to be found in your home.

9. Under what conditions will a liquid wet a solid and spread over it?

10. When will it form in drops on the surface?

11. Explain the proper procedure for removing a grease spot with benzine.

12. What difference is there between a liquid and a fluid?

13. Why cannot a "soap bubble" be blown from pure water?

14. Which are larger, the molecules of steam or those of water? Why?

15. Why is the ground likely to be damp under a stone or board when it is dry all around?

16. Why does any liquid in falling through the air assume the globule form?

17. Give three examples of capillary attraction found in the home. Three out of doors.

18. Why does cultivation of the soil prevent rapid evaporation of water from the ground?