1. The problem statement, all variables and given/known data explain the change in surface tension of mixture of water+alcohol(n-octanol,n-heptanol,n-butanol)? discuss their degree of their solubility in water and this affect to surface tension? 2. Relevant equations L=SURFACE CONCENTRATION δ=SURFACE TENSSION C=CONCENTRATION OF ALCOHOL IN WATER L=(1/RT)*∂δ/∂ln(c) 3. The attempt at a solution If a alcohol is soluble a little in water it can change surface tension so much if a little amount of alcohol is added.