The correct Answer is B
The contact angle is a measurement formed by the balance of energies between the liquid and solid. A higher contact angle means more “bubble-like” and hence poorer wetability.
Surface tension is measured in terms of force (dynes) per centimeter of the surface of liquid. The higher the surface tension, the less the wetability. Some examples at 200 C follow:1-benzene 29 dynes
2-water 72.8
3-mercury 465
These values are influenced by temperature and purity. Higher temperatures and impurities, especially detergents, decrease surface tension. Just remember:
HIGH SURFACE TENSION OR HIGH CONTACT ANGLE = POOR WETABILITY.
Restorative Dental Materials,11th ed. Craig and Powers
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