0722. Solving a chemistry problem

3.11. The contact angle of water on paraffin is 111 at 298 K. For a 0.1 M solution of butylamine in water, the surface tension is 56.3 mJ/m2, the contact angle on paraffin is 92. Calculate the surface tension of the butylamine film adsorbed at the paraffin-water interface . Surface tension of water is 71.96 mJ/m2. Explain how butylamine molecules are oriented in the surface layer. Calculate the work of adhesion.