surface tension

[thebillsfan]

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I know water as a high surface tension. I also know it forms a meniscus when placed in a graduated cyclinder. If water has a high surface tension due to increased intermolecular h bonds then why would it exhibit adhesive tendencies towards the cylinder?

 

[Bernoull]

I know water as a high surface tension. I also know it forms a meniscus when placed in a graduated cyclinder. If water has a high surface tension due to increased intermolecular h bonds then why would it exhibit adhesive tendencies towards the cylinder?

Whether water has "high" surface tension is relative. At 20* C
Water = 72.8 dynes/cm
ethyl alcohol = 22.3 dynes/cm
mercury = 465 dynes/cm

Irrespective of the numeric value of surface tension, the simplest way to understand the meniscus shape is to think about it as a tug-of-war b/t adhesive and cohesive forces. For water in a glass container, adhesive forces are stronger so it curves upwards along the container's walls. For mercury, cohesive forces exceed adhesive ones, and conversely its meniscus curves down at the container interface.

Hope this helps..