How would you calculate the surface tension of a 2% (w/v) solution of a wetting agent that has a density of 1.008 g/mL and that rises 6.6 cm in a capillary tube having an inside radius of 0.2 mm?
The surface tension is
One method to measure the surface tension of a liquid is to measure the height the liquid rises in a capillary tube.
The formula is
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For pure water and clean glass, the contact angle is nearly zero.
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In your problem,
For comparison, the surface tension of pure water at 20 °C is